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1.
Neural Regen Res ; 16(1): 143-149, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32788469

RESUMO

Veins are easy to obtain, have low immunogenicity, and induce a relatively weak inflammatory response. Therefore, veins have the potential to be used as conduits for nerve regeneration. However, because of the presence of venous valves and the great elasticity of the venous wall, the vein is not conducive to nerve regeneration. In this study, a novel tissue engineered nerve graft was constructed by combining normal dissected nerve microtissue with an autologous vein graft for repairing 10-mm peripheral nerve defects in rats. Compared with rats given the vein graft alone, rats given the tissue engineered nerve graft had an improved sciatic static index, and a higher amplitude and shorter latency of compound muscle action potentials. Furthermore, rats implanted with the microtissue graft had a higher density and thickness of myelinated nerve fibers and reduced gastrocnemius muscle atrophy compared with rats implanted with the vein alone. However, the tissue engineered nerve graft had a lower ability to repair the defect than autogenous nerve transplantation. In summary, although the tissue engineered nerve graft constructed with autologous vein and nerve microtissue is not as effective as autologous nerve transplantation for repairing long-segment sciatic nerve defects, it may nonetheless have therapeutic potential for the clinical repair of long sciatic nerve defects. This study was approved by the Experimental Animal Ethics Committee of Chinese PLA General Hospital (approval No. 2016-x9-07) on September 7, 2016.

2.
Neural Regen Res ; 16(2): 319-324, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32859791

RESUMO

Constraint-induced movement therapy (CIMT) can promote the recovery of motor function in injured upper limbs following stroke, which may be associated with upregulation of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) at synapses in the ipsilateral sensorimotor cortex in our previous study. However, AMPAR distribution is tightly regulated, and only AMPARs on the postsynaptic membrane can mediate synaptic transmission. We speculated that synaptic remodeling induced by movement-associated synaptic activity can promote functional recovery from stroke. To test this hypothesis, we compared AMPAR expression on the postsynaptic membrane surface in a rat model of ischemic stroke induced by middle cerebral artery occlusion (MCAO) with versus without CIMT, which consisted of daily running wheel training for 2 weeks starting on day 7 after MCAO. The results showed that CIMT increased the number of glutamate receptor (GluR)2-containing functional synapses in the ipsilateral sensorimotor cortex, and reduced non-GluR2 AMPARs in the ipsilateral sensorimotor cortex and hippocampal CA3 region. In addition, CIMT enhanced AMPAR expression on the surface of post-synaptic membrane in the ipsilateral sensorimotor cortex and hippocampus. Thus, CIMT promotes the recovery of motor function of injured upper limbs following stroke by enhancing AMPAR-mediated synaptic transmission in the ischemic hemisphere. These findings provide supporting evidence for the clinical value of CIMT for restoring limb movement in stroke patients. All experimental procedures and protocols were approved by the Department of Laboratory Animal Science of Fudan University, China (approval No. 201802173S) on March 3, 2018.

3.
Food Chem ; 334: 127608, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711280

RESUMO

Food analysis to ensure food safety and quality are relevant to all countries. This study aimed to develop a detection technique by combining recombinase polymerase amplification with CRISPR-Cas12a for food safety (termed RPA-Cas12a-FS). Our data showed that this novel method could be detected via fluorescence intensity for the molecular identification of foodborne pathogenic bacteria, genetically modified crops, and meat adulteration. After optimization, the sensitivity and stability of RPA-Cas12a-FS was further enhanced. The RPA-Cas12a-FS system could specifically detect target gene levels as low as 10 copies in 45 min at 37 °C. The RPA-Cas12a-FS system was sensitive both using standard samples in the lab and using samples from the field, which indicated that this detection method was practical. In conclusion, a simple, rapid, and highly sensitive detection method based on CRISPR-Cas12a was developed for molecular identification in the food safety field without requiring technical expertise or ancillary equipment.

4.
Food Chem ; 337: 127780, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32799164

RESUMO

To determine malachite green (MG) and its major metabolite, leucomalachite green (LMG) residual levels in tilapia fish, chemiluminescent enzyme immunoassay (CLEIA) was developed based on a single-chain variable fragment (scFv)-alkaline phosphatase (AP) fusion protein. At first, VH and VL gene sequences were cloned from hybridoma cell lines secreting monoclonal antibody against LMG, and then thoroughly by database-assisted sequence analysis. Finally, the productive VH and VL were assembled to an intact scFv sequence and engineered to produce scFv-AP fusion protein. The fusion protein was further identified as a bifunctional reagent for immunoassay, then a sensitive one-step CLEIA against LMG was developed with a half-maximal inhibitory concentration (IC50) and limit of detection (LOD) of 1.3 and 0.04 ng/mL, respectively. The validation results of this novel competitive CLEIA was in line with those obtained by classical HPLC method for determination of total MG in spiked and field incurred samples.

5.
Food Chem ; 336: 127687, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32771901

RESUMO

The electrostatic complex coacervation between scallop Patinopecten. yessoensis male gonad hydrolysates (SMGHs) and κ-carrageenan (κ-C) were monitored by using turbidimetry at various pH (1-12) and biopolymer mixing ratio (9:1-1:9). The pHc exhibited ratio-independent behavior, and pHφ1, pHmax exhibited ratio-dependent behavior, respectively. The decreasing ratio enhanced the gel strength of SMGHs/κ-C at higher pH while inversely at lower pH, ascribing to more SMGHs aggregates and stronger neutralization between positively charged patches in SMGHs and κ-C at lower pH and higher ratio. Moreover, SMGHs/κ-C gel at acid condition exhibited lower relaxation times (T21 and T23). Furthermore, the rheological and relaxation time T2 data were well associated with microscopy images which indicated that SMGHs/κ-C gel showed a well-distributed network structure at more acidic domains, supporting stronger gel rigidity and water-holding capacity.

6.
Mol Med Rep ; 22(5): 3911-3921, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33000186

RESUMO

Osteosarcoma (OS) is a primary malignant tumor of bone tissue. Effective chemotherapy may improve the survival of patients with OS. MicroRNAs (miRs) serve significant roles in the regulatory function of tumorigenesis and chemosensitivity of different types of cancer. miR­22 has been revealed to inhibit the proliferation and migration of OS cells, as well as increasing their sensitivity to cisplatin (CDDP). The mechanisms of action behind the functions of miR­22 in OS drug resistance require investigation. Therefore, in the present study, the human OS cell lines (MG­63, U2OS, Saos2 and OS9901) and a drug­resistant cell line (MG­63/CDDP) were cultured. Cell proliferation, apoptosis and autophagy assays were performed to investigate the proliferation, apoptosis and autophagy of cell lines transfected with miR­22 mimic. Reverse transcription­quantitative polymerase chain reaction and western blot analysis were performed to investigate the expression levels of associated genes. The results revealed that miR­22 inhibited the proliferation of MG­63 cells and MG­63/CDDP cells, and enhanced the anti­proliferative ability of CDDP. miR­22 induced apoptosis and inhibited autophagy of MG­63 cells and MG­63/CDDP cells. Apoptosis­related genes, including caspase­3 and Bcl­2­associated X protein were upregulated, while B­cell lymphoma­2 was downregulated in both cell lines transfected with the miR­22 mimic. Autophagy protein 5, beclin1 and microtubules­associated protein 1 light chain 3 were downregulated in both cell lines transfected with miR­22 mimic. Furthermore, the in vitro and in vivo expression levels of metadherin (MTDH) in the OS/OS­CDDP­resistant models were downregulated following transfection with the miR­22 mimic. Therefore, the results of the present study suggested that miR­22 promoted CDDP sensitivity by inhibiting autophagy and inducing apoptosis in OS cells, while MTDH may serve a positive role in inducing CDDP resistance of OS cells.

7.
PLoS One ; 15(10): e0239723, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33006996

RESUMO

BACKGROUND: Allergic rhinitis (AR) is a burdensome respiratory disorder whose etiology and pathophysiology remain controversial and most likely multifactorial. Accumulated evidence indicates that gut dysbiosis contributes to AR via the gut-airway axis. Constipation could result in alteration of the intestinal microflora. The clinical impact of constipation on AR has not been studied. We aimed to evaluate the risk of AR in constipated patients using a nationwide longitudinal population-based cohort. METHODS: We identified 57786 patients with constipation and 57786 matched controls between 1999 and 2013 from the Longitudinal Health Insurance Database, which is a subset of Taiwanese National Health Insurance Research Database. Propensity score analysis was used for matching age, sex, comorbidities, and medications at a ratio of 1:1. Multiple Cox regression and subgroup analyses were used to estimate the adjusted hazard ratio of AR. RESULTS: The incidence of AR was 32.2 per 1,000 person-years in constipated patients, which was twice that of non-constipated patients. After adjustment for patients' age, gender, comorbidities, and medications, patients with constipation had a 2.3-fold risk of AR compared to those without constipation (adjusted hazard ratio [aHR]: 2.30; 95% CI, 2.23-2.37). In subgroup analyses, patients aged 20-39 years had a 2.24-fold higher risk of AR in the constipation cohort (aHR; 95% CI, 2.12-2.36). Patients aged <20, 40-64, and ≥65 years had a 2.09, 2.05, and 2.07-fold risk of AR in the constipation cohort, respectively (aHR; 95% CI, 1.98-2.20, 1.94-2.18, and 1.92-2.23). Also, patients with constipation had a higher likelihood of AR, regardless of sex, and with or without comorbidities including hyperlipidemia, hypertension, chronic kidney disease, chronic liver disease, diabetes, chronic obstructive pulmonary disease, rheumatoid arthritis, dyspepsia, irritable bowel syndrome, and anxiety. CONCLUSION: Constipation might be associated with an increased risk of incidental AR. It seems that physicians should keep a higher index of suspicion for AR in people with constipation. The patency issue of gut could not be ignored in patients with AR.

8.
BMJ Open ; 10(10): e037514, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020094

RESUMO

INTRODUCTION: Cognitive behavioural therapy (CBT) is an evidence-based treatment for adults with attention deficit hyperactivity disorder (ADHD). However, it is still inconsistent whether a combination of CBT would have additive effects in medicated ADHD in adulthood. And if CBT would have additional effects, what kind and which dimension would CBT play a part? This study estimates the efficacy of CBT in stable medicated adult ADHD, using long-term outcomes and multidimensional evaluations. METHODS AND ANALYSIS: It is a two-armed, randomised controlled trial on the superiority of the efficacy of 12 weeks of CBT on medicated adult ADHD. We compare the short-term and long-term outcomes between CBT combined with medication (CBT+M) group and the medication-only (M) group, including ADHD core symptoms, emotional symptoms, executive function, self-esteem, life quality and brain function using functional near-infrared spectroscopy data. Participants are outpatients of the Peking University Sixth Hospital and those recruited online, diagnosed as adult ADHD and with stable medication treatment. We estimate ADHD core symptoms and combined symptoms at baseline (T1) and week 12 (T2), week 24 (T3), week 36 (T4) and week 48 (T5). ETHICS AND DISSEMINATION: This trial has been approved by the Ethics and Clinical Research Committees of Peking University Sixth Hospital and will be performed under the Declaration of Helsinki with the Medical Research Involving Human Subjects Act (WMO). The results will be disseminated in a peer-reviewed journal and a conference presentation. TRIAL REGISTRATION NUMBER: ChiCTR (ChiCTR1900021705).

9.
Psychol Med ; : 1-10, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33032665

RESUMO

BACKGROUND: The Cognitive Battery of the National Institutes of Health Toolbox (NIH-TB) is a collection of assessments that have been adapted and normed for administration across the lifespan and is increasingly used in large-scale population-level research. However, despite increasing adoption in longitudinal investigations of neurocognitive development, and growing recommendations that the Toolbox be used in clinical applications, little is known about the long-term temporal stability of the NIH-TB, particularly in youth. METHODS: The present study examined the long-term temporal reliability of the NIH-TB in a large cohort of youth (9-15 years-old) recruited across two data collection sites. Participants were invited to complete testing annually for 3 years. RESULTS: Reliability was generally low-to-moderate, with intraclass correlation coefficients ranging between 0.31 and 0.76 for the full sample. There were multiple significant differences between sites, with one site generally exhibiting stronger temporal stability than the other. CONCLUSIONS: Reliability of the NIH-TB Cognitive Battery was lower than expected given early work examining shorter test-retest intervals. Moreover, there were very few instances of tests meeting stability requirements for use in research; none of the tests exhibited adequate reliability for use in clinical applications. Reliability is paramount to establishing the validity of the tool, thus the constructs assessed by the NIH-TB may vary over time in youth. We recommend further refinement of the NIH-TB Cognitive Battery and its norming procedures for children before further adoption as a neuropsychological assessment. We also urge researchers who have already employed the NIH-TB in their studies to interpret their results with caution.

11.
J Ethnopharmacol ; : 113438, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33017635

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The roots of Rubia yunnanensis Diels (Chinese name 'Xiao-Hong-Shen'), a traditional Chinese medicine native to Yunnan province (China), have a long history of use for treating several diseases, such as tuberculosis, rheumatism and cancers. A bicyclic hexapeptidic glucoside named RA-XII was isolated from R. yunnanensis, which has been reported to exert anti-inflammatory and antitumor activities. AIM OF THE STUDY: This study was designed to investigate the antitumor activity and potential mechanism of RA-XII on colorectal cancer (CRC) cell lines. MATERIALS AND METHODS: Sulforhodamine B assay, clonogenic assay and cell cycle analysis were conducted to assess the anti-proliferative activity of RA-XII on CRC cells. GFP-LC3B plasmid transfection, MDC and AO staining assays, cathepsin activity assay, and siRNAs against several genes were used to investigate the effect of RA-XII on autophagy. Western blotting was used to examine the expression levels of proteins associated with cell cycle arrest, apoptosis and autophagy. Human CRC xenograft-bearing BALB/c nude mice were used to evaluate the antitumor effect of RA-XII in vivo. RESULTS: RA-XII showed favorable antineoplastic activity in SW620 and HT29 cells in vitro and in vivo. RA-XII did not induce apoptosis indicated by no obvious changes on mitochondrial membrane potential and apoptosis-related marker proteins in SW620 or HT29 cells. Treatment of RA-XII inhibited the formation of autophagosomes, which is implied by the GFP-LC3 fluorescent dots, MDC-stained autophagic vesicles and LC3 protein expression. It was indicated that RA-XII suppressed autophagy by regulating several signaling pathways including mTOR and NF-κB pathways. Pharmacological or genetic inhibition of autophagy could enhance the cytotoxicity of RA-XII while autophagy inducer could rescue RA-XII-induced cell death. Besides, RA-XII could increase the susceptibility of CRC cells to bortezomib. CONCLUSION: Our study demonstrated that RA-XII exerted antitumor activity independent of apoptosis, and suppressed protective autophagy by regulating mTOR and NF-κB pathways in SW620 and HT29 cell lines, which suggested that RA-XII is a key active ingredient for the cancer treatment of Rubia yunnanensis and possesses a promising prospect as an autophagy inhibitor for CRC therapy.

12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4200-4203, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33018923

RESUMO

This paper presents a novel lead body design for active implantable medical devices (AIMD) to reduce Radio-frequency (RF) induced heating during magnetic resonance imaging (MRI) scanning. By introducing a counterpoise electrode to the original lead construct, part of the RF-induced energy can be decoyed into the surrounding tissues while the therapy signal is intact. The numerical simulation studies of three leads with different configurations are presented to demonstrate the effectiveness of this technique. From simulation results at 1.5 T, the peak 1g average SAR value can be reduced by a factor of 3 when the length of the counterpoise electrode is properly designed.

13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4728-4731, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33019047

RESUMO

It is quite a challenge on positioning surgical robot to optimal place in a crowded and special environment. Compared with the structured industrial environment, the unstructured operating room (OR) environment brings higher requirements for safety of the surgical robot. Meanwhile, the efficiency has significant impact on the ease of surgical robot and repositioning requires additional time and labor. This paper introduces a new method of pose and layout planning to deal with the problem of interaction between robot and environment in operating room. The optimal layout and working pose planning of robot in OR environment are accomplished through APF calculation, pose traversal and layout traversal. The feasibility of this method is validated in simulated OR environment.

14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4951-4954, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33019098

RESUMO

In the current research of prosthetic hands, many degrees of freedom have been omitted in order to simplify the design and reduce the weight, such as the abduction degrees of freedom of the four fingers except the thumb, which impairs the range of mobility of the prosthetic hand to some extent. This paper presents TN hand, a 3D printed, tendon-driven prosthetic hand. We use continuum structure as the finger joint. The other four fingers except the middle finger can perform flexion/extension and abduction/adduction movements, which benefits hand mobility. The design and manufacture of the fingers were elaborated and the finger stiffness was tested through experiment. Then the ability of manipulating daily objects of TN hand was verified based on hand taxonomy. In addition, there is enough range of mobility for the TN hand to perform column chords due to the ability to abduct fingers.

15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5482-5485, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33019220

RESUMO

Acute leukemia often comes with life-threatening prognosis outcome and remains a critical clinical issue today. The implementation of measurable residual disease (MRD) using flow cytometry (FC) is highly effective but the interpretation is time-consuming and suffers from physician idiosyncrasy. Recent machine learning algorithms have been proposed to automatically classify acute leukemia samples with and without MRD to address this clinical need. However, most prior works either validate only on a small data cohort or focus on one specific type of leukemia which lacks generalization. In this work, we propose a transfer learning approach in performing automatic MRD classification that takes advantage of a large scale acute myeloid leukemia (AML) database to facilitate better learning on a small cohort of acute lymphoblastic leukemia (ALL). Specifically, we develop a knowledge-reserved distilled AML pre-trained network with ALL complementary learning to enhance the ALL MRD classification. Our framework achieves 84.5% averaged AUC which shows its transferability across acute leukemia, and our further analysis reveals that younger and elder ALL patient samples benefit more from using the pre-trained AML model.

16.
Clin Exp Immunol ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020903

RESUMO

Young donors are reported to be associated with better transplant outcomes than old donors in allogeneic hematopoietic stem cell transplantation (allo-HSCT), but the mechanism is still unclear. The current study compared the different subsets of haematopoietic stem cells (HSCs) and their progenitors as well as immune cells in bone marrow (BM) between young and old donors. The frequencies of HSCs, multipotent progenitors (MPPs) and myeloid progenitors, including common myeloid progenitors (CMPs) and megakaryocyte-erythroid progenitors (MEPs), were decreased, whereas those of lymphoid progenitors, including multipotent lymphoid progenitors (MLPs) and common lymphoid progenitors (CLPs), were increased in the BM of young donors compared with in that of old donors. Lower reactive oxygen species (ROS) levels were observed in BM HSCs and six progenitor lines in young donors. Furthermore, young donors demonstrated higher frequencies of naïve T cells and immune suppressor cells, such as alternative macrophages (M2), and lower frequencies of memory T cells and immune effectors, including T helper-1 and T cytotoxic-1 cells, in BM than old donors. Multivariate analysis demonstrated that donor age was independently correlated with BM HSC frequency. Although further validation is required, our results suggest that the differences in the frequency and immune differentiation potential of HSCs in BM between young donors and old donors may partly explain the different outcomes of allo-HSCT.

17.
J Cardiothorac Surg ; 15(1): 296, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008451

RESUMO

BACKGROUND: The Surgical Pleth Index (SPI) is a monitoring method that reflects painful stimuli during general anesthesia, and dexmedetomidine is an analgesic adjuvant with an opioid-sparing effect. But up to now, it is still unclear whether dexmedetomidine has any influence on SPI. To investigate whether dexmedetomidine has an effect on SPI during video-assisted thoracoscopic surgery. METHODS: We enrolled 94 patients who underwent video-assisted thoracoscopic lung lobectomy. Patients were randomly assigned to a dexmedetomidine group (dexmedetomidine: 0.8 µg/kg administered for 10 min before anesthesia) or normal saline group (equal volume of normal saline). SPI and vital signs were recorded. The number rating scale (NRS) pain score was also evaluated. RESULTS: SPI values were significantly lower in the dexmedetomidine group than in the normal saline group at intubation and at discharge from the postanesthesia care unit. Compared with the normal saline group, mean arterial pressure and heart rate were both significantly lower in the dexmedetomidine group at intubation. Heart rate was lower at skin incision in the dexmedetomidine group. The NRS score in the normal saline group was noticeably higher vs. the dexmedetomidine group at discharge from the postanesthesia care unit. CONCLUSIONS: Dexmedetomidine decreased intraoperative SPI and NRS scores. Our results showed that dexmedetomidine attenuated noxious stimuli. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR): ChiCTR-OOC-16009450 , Registered 16 October, 2016.


Assuntos
Analgésicos não Entorpecentes/uso terapêutico , Dexmedetomidina/uso terapêutico , Pneumopatias/cirurgia , Adolescente , Adulto , Idoso , Anestesia Geral , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória , Pneumonectomia , Estudos Prospectivos , Cirurgia Torácica Vídeoassistida , Adulto Jovem
18.
Nat Commun ; 11(1): 5005, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024109

RESUMO

Hypoxia-inducible factor 1α (HIF-1α) and HIF-2α are master transcription factors that regulate cellular responses to hypoxia, but the exact function in regulatory T (Treg) cells is controversial. Here, we show that Treg cell development is normal in mice with Foxp3-specific knockout (KO) of HIF-1α or HIF-2α. However, HIF-2α-KO (but not HIF-1α-KO) Treg cells are functionally defective in suppressing effector T cell-induced colitis and inhibiting airway hypersensitivity. HIF-2α-KO Treg cells have enhanced reprogramming into IL-17-secreting cells. We show crosstalk between HIF-2α and HIF-1α, and that HIF-2α represses HIF-1α expression. HIF-1α is upregulated in HIF-2α-KO Treg cells and further deletion of HIF-1α restores the inhibitory function of HIF-2α-KO Treg cells. Mice with Foxp3-conditional KO of HIF-2α are resistant to growth of MC38 colon adenocarcinoma and metastases of B16F10 melanoma. Together, these results indicate that targeting HIF-2α to destabilize Treg cells might be an approach for regulating the functional activity of Treg cells.

19.
Food Funct ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026005

RESUMO

Antibiotics are used worldwide to treat diseases in humans and other animals; most of them and their secondary metabolites are discharged into the aquatic environment, posing a serious threat to human health. However, the toxicity of antibiotics on aquatic organisms, especially the effects on the detoxification system and immune system, has not been thoroughly studied. Lycopene (LYC) is a naturally occurring hydrocarbon carotenoid, which has received extensive attention as a potential antioxidant. The aim of this study was to investigate whether LYC alleviates exogenous toxicity in carp induced by sulfamethoxazole (SMZ) and the underlying molecular mechanisms. The grass carp were treated with SMZ (0.3 µg L-1) and/or LYC (10 mg per kg body weight) for 30 days. Indexes, such as hepatic function-related including histopathological changes and biochemical parameters, detoxification system-related including the cytochrome P450 enzyme system and antioxidant system, and immune system-related including inflammatory and apoptosis processes were detected. The results showed that SMZ stress leads to significant pathological damage of the liver and induction of oxidative stress. LYC coadministration recovered the cytochrome p450-1A1 homeostasis and decreased SMZ-induced accumulation of intracellular reactive oxygen species (ROS). Mechanistically, indicators in the innate immune system (such as toll like receptors (TLRs), tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6 and IL-8) and the apoptosis pathway (p53, PUMA, B-cell lymphoma-2 (Bcl-2), BCL2-associated X (Bax), and Caspase-9/3) disclosed adaptive activation under SMZ exposure; these anomalies returned to normal or close-to-normal levels after LYC coadministration. Therefore, LYC dietary supplement possesses liver protective function against exogenous toxic compounds like SMZ, making LYC a functional aquatic feed ingredient for aquiculture.

20.
J Exp Bot ; 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33005924

RESUMO

Acyl-CoA: diacylglycerol acyltransferase (DGAT) catalyzes the final committed step in triacylglycerol (TAG) biosynthesis in eukaryotes. In microalgae, the copy number of DGAT genes is extraordinarily expanded and yet the functions of many DGATs remain largely unknown. This study revealed microalgal DGAT can function as lysophosphatidic acyltransferase (LPAAT) both in vitro and in vivo while losing its original function as DGAT. Among the five DGAT encoding genes identified and cloned from the green microalga Haematococcus pluvialis, four encodes HpDGATs that showed TAG synthase activities in yeast for functional complementation analysis, except for one of the type II DGAT encoding genes, i.e., HpDGTT2 gene. The hydrophobic recombinant HpDGTT2 was purified in a soluble form and was revealed to function as a LPAAT via enzymatic assay. Introducing this gene into the green microalga Chlamydomonas reinhardtii led to retarded cellular growth, enlarged cell size and enhanced TAG accumulation, identical to the phenotypes of the transgenic strains with overexpressed CrLPAAT. This study provides a framework for dissecting uncharacterized DGATs, and could pave the way to decrypt the structure-function relationship of this large group of enzymes critical to lipid biosynthesis.

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