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1.
Nat Genet ; 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33875864

RESUMO

The evolutionary and genetic origins of the specialized body plan of flatfish are largely unclear. We analyzed the genomes of 11 flatfish species representing 9 of the 14 Pleuronectiforme families and conclude that Pleuronectoidei and Psettodoidei do not form a monophyletic group, suggesting independent origins from different percoid ancestors. Genomic and transcriptomic data indicate that genes related to WNT and retinoic acid pathways, hampered musculature and reduced lipids might have functioned in the evolution of the specialized body plan of Pleuronectoidei. Evolution of Psettodoidei involved similar but not identical genes. Our work provides valuable resources and insights for understanding the genetic origins of the unusual body plan of flatfishes.

2.
Proc Natl Acad Sci U S A ; 118(16)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33853952

RESUMO

Photosynthesis of hydrogen peroxide (H2O2) in ambient conditions remains neither cost effective nor environmentally friendly enough because of the rapid charge recombination. Here, a photocatalytic rate of as high as 114 µmol⋅g-1⋅h-1 for the production of H2O2 in pure water and open air is achieved by using a Z-scheme heterojunction, which outperforms almost all reported photocatalysts under the same conditions. An extensive study at the atomic level demonstrates that Z-scheme electron transfer is realized by improving the photoresponse of the oxidation semiconductor under visible light, when the difference between the Fermi levels of the two constituent semiconductors is not sufficiently large. Moreover, it is verified that a type II electron transfer pathway can be converted to the desired Z-scheme pathway by tuning the excitation wavelengths. This study demonstrates a feasible strategy for developing efficient Z-scheme photocatalysts by regulating photoresponses.

3.
Plant Physiol ; 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33848345

RESUMO

Plants use a dual defense system to cope with microbial pathogens. The first involves pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) which is conferred by membrane receptors, and the second involves effector-triggered immunity (ETI), which is conferred by disease-resistance proteins (nucleotide-binding leucine-rich repeat containing proteins; NLRs). Calmodulin-Binding Protein 60 (CBP60) family transcription factors are crucial for pathogen defense: CBP60g and Systemic Acquired Resistance Deficient 1 (SARD1) positively regulate immunity, whereas CBP60a negatively regulates immunity. The roles of other Arabidopsis (Arabidopsis thaliana) CBP60s remain unclear. We report that CBP60b positively regulates immunity, and is redundant with-yet distinct from-CBP60g and SARD1. By combining ChIP-PCRs and luciferase (LUC) reporter assays, we demonstrate that CBP60b is a transcriptional activator of immunity genes. Surprisingly, CBP60b loss-of-function results in autoimmunity, exhibiting a phenotype similar to that of CBP60b gain-of-function. Mutations at the EDS1-PAD4-dependent (ENHANCED DISEASE SUSCEPTIBILITY 1- PHYTOALEXIN DEFICIENT 4) ETI pathway fully suppressed the defects of CBP60b loss-of-function but not those of CBP60b gain-of-function, suggesting that CBP60b is monitored by NLRs. Functional loss of SUPPRESSOR OF NPR1-1, CONSTITUTIVE 1 (SNC1), an R-gene, partially rescued the phenotype of cbp60b, further supporting that CBP60b is a protein targeted by pathogen effectors, i.e., a guardee. Unlike CBP60g and SARD1, CBP60b is constitutively and highly expressed in unchallenged plants. Transcriptional and genetic studies further suggest that CBP60b plays a role redundant with CBP60g and SARD1 in pathogen-induced defense, whereas CBP60b has a distinct role in basal defense, partially via direct regulation of CBP60g and SARD1.

4.
Zhongguo Gu Shang ; 34(4): 354-9, 2021 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-33896136

RESUMO

OBJECTIVE: To compare the clinical effects of different anterior surgical methods in treating single segment cervical disc herniation. METHODS: The clinical data of 46 patients with single-segment cervical disc herniation underwent surgical treatment from September 2013 to September 2018 were retrospectively analyzed. The patients were divided into three groups according to different surgical methods. Among them, 23 patients in the anterior percutanousendomic cervical dissection (APECD) group, there were 8 males and 15 females, aged (47±3) years old, prominent segments were C3,4 of 1 case, C4,5 of 6 cases, and C5,6 of 16 cases;10 patients in cervical disc replacement(CDR) group, there were 4 males and 6 females, aged (46± 3) years old, prominent segments were C3,4 of 1 case, C4,5 of 6 cases, C5,6 of 3 cases;13 patients in transcervical anterior cervical disc fusion (ACDF) group, there were 8 males and 5 females, aged (53±2) years old, protruding segments were C3,4 of 1 case, C4,5 of 3 cases, C5,6 of 9 cases. The operation time, intraoperative blood loss, and length of hospitalization were compared among three groups;visual analogue scale (VAS) and Japanese Orthopaedic Association(JOA) score were used to evaluate the clinical efficacy. RESULTS: All 46 patients were followed up for 12 to 24 (17.57±3.15)months. The follow-up time of APECD, CDR, ACDF groups were (17.30±3.25), (17.80±3.16), (17.85±2.88) months, and operation time were (95.48 ±13.85), (58.50±7.09), (76.00±15.72) min, respectively, there were no significant differences in follow-up time and operation time between two groups(P>0.05). The intraoperative blood loss of APECD, CDR, ACDF groups were (80.00±20.22), (82.60±7.20), (121.54±18.75) ml, there was significant difference between CDR group and ACDF group (P<0.05);and there was no significant difference between other groups (P>0.05). The length of hospitalization was (6.95±1.50) days in APECD group, (6.60± 0.80) days in CDR group, (6.54±0.75) days in ACDF group, and there was no significant difference between two groups (P> 0.05). At the latest follow up, VAS scores were decreasedfrom preoperative 6.78±0.83 to 2.57±0.65 in APECD group, decreased from 5.70±0.78 to 2.00±0.45 in CDR group, decreased from 6.77±0.42 to 1.38±0.49 in ACDF group. The JOA scores at final follow-up were increased from 8.91±0.97 to 13.04±1.40 in APECD group, and the improvement rate of (65±15)%;increased from 11.50±1.20 to 14.90±1.14 in CDR group, and the improvement rate of (76±19)%;increased from 8.54±0.93 to 14.00±0.96 in ACDF group, and the improvement rate of (74±8)%;there was significant difference in improvement rate between APECD group and CDR group (P<0.05). At final follow-up, the activities of the responsible segment in APECD group and CDR group were well preserved and improved (P<0.05). In the APECD group, the symptoms of two cases recurred during the mid-term follow-up (4 months and 6 months after surgery), one of which improved after strictly conservative treatment;the other one received ACDF surgery a second time, and the postoperative follow-up effect was satisfactory. CONCLUSION: The three anterior surgical approaches can achieve satisfactory clinical results for the treatment of single-segment cervical disc herniation. However, the improvement rate of the CDR group and the activity of the retained responsibility segment are better than those of the other two groups. APECD surgery may have recurrence.


Assuntos
Degeneração do Disco Intervertebral , Fusão Vertebral , Substituição Total de Disco , Adulto , Vértebras Cervicais/cirurgia , Discotomia , Feminino , Seguimentos , Humanos , Degeneração do Disco Intervertebral/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
5.
Biochem Pharmacol ; 188: 114575, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33887260

RESUMO

Hyperactivation of signal transducer and activator of transcription 3 (STAT3) is strongly associated with cancer initiation, progression, metastasis, chemoresistance, and immune evasion; thus, STAT3 has been intensely studied as a therapeutic target for cancer treatment. Berberine (BBR), an active component extracted from Coptis chinensis, has shown anti-tumor effects in multiple tumors. However, its underlying mechanisms have not yet been fully elucidated. In this study, we investigated the effects and the underlying mechanisms of BBR on bladder cancer (BCa) cells. We found that BBR showed significant cytotoxic effects against BCa cell lines both in vivo and in vitro, with much lower cytotoxic effects on the human normal urothelial cell line SV-HUC-1. BBR treatment induced DNA replication defects and cell cycle arrest, resulting in apoptosis or cell senescence, depending on p53 status, in BCa cells. Mechanistically, BBR exerted anti-tumor effects on BCa cells by inhibiting Janus kinase 1 (JAK1)-STAT3 signaling through the upregulation of miR-17-5p, which directly binds to the 3'UTR of JAK1 and STAT3, downregulating their expressions. Collectively, our results demonstrate that BBR exerts anti-tumor effects by perturbing JAK1-STAT3 signaling through the upregulation of miR-17-5p in BCa cells, and that BBR may serve as a potential therapeutic option for BCa treatment.

6.
Adv Mater ; : e2007368, 2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33893666

RESUMO

Behaving as structural protectors and electronic modulators, catalyst supports such as graphene derivatives are generally constructed by covalent bonds. Here, hydrogen-bonded ultrathin nanosheets are reported as a new type of catalyst support. Melamine (M) and cyanuric acid (CA) molecules self-assemble to form the graphite-like hydrogen-bonded co-crystal M-CA, which can be easily exfoliated by ultrasonic treatment to yield ultrathin nanosheets with thickness of ≈1.6 nm and high stability at pH = 0. The dynamic nanosheets form adaptive defects/pores in the synthetic process of CoP nanoparticles, giving embedded composite with high hydrogen evolution activity (overpotential of 66 mV at 10 mA cm-2 ) and stability. Computational calculations, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy unveil the electron modulation effects of the nanosheets. This pseudo-porous catalyst support also can be applied to other metal phosphides.

7.
Zhongguo Zhong Yao Za Zhi ; 46(6): 1357-1367, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33787132

RESUMO

The growth years of traditional Chinese medicinal materials are closely related to their quality, which directly affects the efficacy and safety of clinical medication. Therefore, it is particularly important to establish an identification method for the growth years of traditional Chinese medicinal materials. In this review, the identification methods for the growth years of traditional Chinese medicinal materials were summarized systematically, and were divided into four types according to the identification principles and methods: traditional identification, molecular identification, physical/chemical identification, and integrated identification. Relying on rich experience, objective molecular markers, various physical/chemical methods and integrated identification techniques(including infrared spectroscopy, nuclear magnetic resonance spectroscopy, high performance liquid chromatography, gas chromatography, mass spectrometry, bionic identification technology and their tandem technologies, etc.), the differences of characters or chemical fingerprints were compared in depth. The growth years of traditional Chinese medicinal materials were quickly identified or predicted by the appearance and characters, the whole fingerprint information or the content of specific chemical markers, and their content ratios. Through the case analysis of mature varieties, we intend to promote the establishment of a perfect technology system for the identification of the growth years of traditional Chinese medicinal materials, and to provide a reference for other perennial herbal materials, finally resulting in the accurate and precise quality control of traditional Chinese medicinal materials.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , China , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos
8.
Org Lett ; 23(7): 2807-2810, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33755492

RESUMO

Fortuneicyclidins A (1) and B (2), a pair of epimeric pyrrolizidine alkaloids containing an unprecedented 7-azatetracyclo[5.4.3.0.02,8]tridecane core, were isolated from the seeds of Cephalotaxus fortunei, along with two biogenetically relative known analogues, 3 and 4. The structures were determined by multiple spectral techniques and chemical derivatization methods. Compound 1 showed inhibitory activity against α-glucosidase.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33738801

RESUMO

OBJECTIVE: The aim of this study was to establish a preoperative prediction method for sparsely granulated (SG) growth hormone (GH) secreting pituitary adenoma, an aggressive tumor subtype with high recurrence risk, in acromegaly patients. METHODS: Eighty-three patients with GH-secreting pituitary adenomas were included in this study. GH measurements, cytokeratin immunostaining and electron microscopy were performed to detect granulation patterns. Preoperative factors, including general, radiological and endocrinological features and acute octreotide suppression test outcomes, were compared between SG and densely granulated (DG) groups. The predictive capabilities of these features were analyzed using a receiver operating characteristic (ROC) curve, and the most predictive features were combined to establish a grading scale. RESULTS: Thirty-nine of the 83 patients had SG GH-secreting pituitary adenomas; 44 had DG tumors. SG tumors tended to occur in younger patients and have larger diameters and volumes, higher Knosp grades, lower GH indexes and normalized insulin-like growth factor-1 (IGF-1) levels, and a lower ∆GH% after octreotide treatment. The tumor size, Knosp grade, GH index and ∆GH% after octreotide treatment had good predictive performance, with area under the curve (AUC) values ranging from 0.70 to 0.80. Combining four parameters, including diameter, Knosp grade, GH index and ∆GH% after octreotide treatment, we established a grading scale for predicting SG GH-secreting pituitary adenomas with an AUC of 0.84 and relatively high sensitivity and specificity. CONCLUSIONS: We propose a predictive method for distinguishing SG and DG GH-secreting pituitary adenomas preoperatively. This method will help physicians identify candidates for presurgical medical treatment and neurosurgeons determine radical surgical strategies for high-risk tumors.

10.
Org Lett ; 23(6): 2342-2346, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33683897

RESUMO

Rifamycins have been clinically utilized against mycobacterial infections for more than 50 years; however, their biosynthesis has not been fully elucidated. Here, on the basis of in vivo gene deletions, in vitro enzyme assays, isotope labeling, and site-directed mutations, we found that a flavin-dependent monooxygenase encoded by a rifamycin biosynthetic gene cluster, Rif-Orf17, not only converted the naphthoquinone chromophore of rifamycin S into benzo-γ-pyrone but also linearized rifamycin SV through phenolic hydroxylation. Both oxidation routes lead to inactivation of rifamycins.

11.
Acta Pharmacol Sin ; 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33686245

RESUMO

Aristolochic acid I (AAI) is a well-known nephrotoxic carcinogen, which is currently reported to be also associated with hepatocellular carcinoma (HCC). Whether AAI is a direct hepatocarcinogen remains controversial. In this study we investigated the association between AAI exposure and HCC in adult rats using a sensitive rat liver bioassay with several cofactors. Formation of glutathione S-transferase placental form-positive (GST-P+) foci was used as the marker for preneoplastic lesions/clonal expansion. We first conducted a medium-term (8 weeks) study to investigate whether AAI had any tumor-initiating or -promoting activity. Then a long-term (52 weeks) study was conducted to determine whether AAI can directly induce HCC. We showed that oral administration of single dose of AAI (20, 50, or 100 mg/kg) in combination with partial hepatectomy (PH) to stimulate liver proliferation did not induce typical GST-P+ foci in liver. In the 8-week study, only high dose of AAI (10 mg · kg-1 · d-1, 5 days a week for 6 weeks) in combination with PH significantly increased the number and area of GST-P+ foci initiated by diethylnitrosamine (DEN) in liver. Similarly, only high dose of AAI (10 mg· kg-1· d-1, 5 days a week for 52 weeks) in combination with PH significantly increased the number and area of hepatic GST-P+ foci in the 52-week study. No any nodules or HCC were observed in liver of any AAI-treated groups. In contrast, long-term administration of AAI (0.1, 1, 10 mg· kg-1· d-1) time- and dose-dependently caused death due to the occurrence of cancers in the forestomach, intestine, and/or kidney. Besides, AAI-DNA adducts accumulated in the forestomach, kidney, and liver in a time- and dose-dependent manner. Taken together, AAI promotes clonal expansion only in the high-dose group but did not induce any nodules or HCC in liver of adult rats till their deaths caused by cancers developed in the forestomach, intestine, and/or kidney. Findings from our animal studies will pave the way for further large-scale epidemiological investigation of the associations between AA and HCC.

12.
Biomed Pharmacother ; 138: 111441, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33652261

RESUMO

Metabolic syndrome (MetS) is a complex, multifactorial disease which lead to an increased risk of cardiovascular disease, type 2 diabetes, and stroke. However, selective, and potent drugs for the treatment of MetS are still lacking. Previous studies have found that Akebia saponin D (ASD) has beneficial effects on metabolic diseases such as obesity, atherosclerosis, and non-alcoholic fatty liver disease (NAFLD). Therefore, our study was designed to determine the effect and mechanism of action of ASD against MetS in a high-fat diet (HFD) induced mouse model. ASD significantly decreased plasma lipid and insulin resistance in these mice, and a targeted approach using metabolomic analyses of plasma and feces indicated that glucose and lipids in these mice crossed the damaged intestinal barrier into circulation. Furthermore, ASD was able to increase lipid excretion and inhibit intestinal epithelial lipid absorption. Results for gut microbiota composition showed that ASD significantly reduced HFD-associated Alistipes, Prevotella, and enhanced the proportions of Butyricimonas, Ruminococcus, and Bifidobacterium. After 14 weeks of ASD/fecal microbiota transplantation (FMT) interventions the developed gut barrier dysfunction was restored. Additionally, RNA-seq revealed that ASD reduced the lipid-induced tight junction (TJ) damage in intestinal epithelial cells via down-regulation of the PPAR-γ-FABP4 pathway in vitro and that use of the PPAR-γ inhibitor (T0070907) was able to partially block the effects of ASD, indicating that the PPAR-γ/FABP4 pathway is a critical mediator involved in the improvement of MetS. Our results demonstrated that ASD not only modifies the gut microbiome but also ameliorates the HFD-induced gut barrier disruption via down-regulation of the PPAR-γ-FABP4 pathway. These findings suggest a promising, and novel therapeutic strategy for gut protection against MetS.

13.
Environ Sci Technol ; 55(8): 5393-5402, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33729752

RESUMO

FeNX in Fe single-atom catalysts can be the active site for adsorption and activation of reactants. In addition, FeNX species have been shown to facilitate electron transfer between Fe and the carbon supports used in newly developed metal-air batteries. We hypothesized that the combination of FeNX species with granular zero-valent iron (ZVI) might result in catalyzed reductive decontamination of groundwater contaminants such as trichloroethylene (TCE). Here, such materials synthesized by ball milling microscale ZVI with melamine and the resulting N species were mainly in the form of pyridinic, pyrrolic, and graphitic N. This new material (abbreviated as N-C-mZVIbm) dechlorinated TCE at higher rates than bare mZVIbm (about 3.5-fold) due to facilitated electron transfer through (or around) the surface layer of iron oxides by the newly formed Fe-NX(C). N-C-mZVIbm gave higher kTCE (0.4-1.14 day-1) than mZVIbm (0-0.4 day-1) over a wide range of pH values (4-11). Unlike most ZVI systems, kTCE for N-C-mZVIbm increased with increasing pH values. This is because the oxide layer that passivates Fe0 at a high pH is disrupted by Fe-NX(C) formed on N-C-mZVIbm, thereby allowing TCE dechlorination and HER under basic conditions. Serial respike experiments gave no evidence of decreased performance of N-C-mZVIbm, showing that the advantages of this material might remain under field applications.


Assuntos
Água Subterrânea , Tricloroetileno , Poluentes Químicos da Água , Concentração de Íons de Hidrogênio , Ferro , Tricloroetileno/análise , Poluentes Químicos da Água/análise
14.
Behav Brain Res ; 405: 113200, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33636237

RESUMO

Traumatic brain injury (TBI) is an increasingly common emergency disease that usually leads to prolonged physical and cognitive impairments. In this study, we investigated if sevoflurane could induce cognitive improvement in TBI rats. Rats were subjected to head trauma induced by a fluid percussion device. A two-hour exposure to 3% sevoflurane was performed in a chamber immediately after TBI. Sevoflurane inhalation reduced the neurological and cognitive deficits induced by TBI with ameliorated synaptic injuries in the hippocampus. Moreover, after sevoflurane treatment, the expression of nuclear factor erythroid-2-related factor-2 (Nrf-2) and hemeoxygenase-1 (HO-1) in the hippocampus was enhanced 1 d after TBI and maintained at high levels 14 days later, and oxidative stress induced by TBI was inhibited. However, the HO-1 inhibitor, Zinc protoporphyrin (ZnPP), used to demonstrate the involvement of HO-1, suppressed the protective effect of sevoflurane. These results indicate that sevoflurane administered immediately after TBI may protect against TBI-induced synaptic and cognitive impairments by promoting the antioxidant Nrf-2/HO-1 pathway. Sevoflurane may be a promising anesthetic for patients with TBI.

15.
Poult Sci ; 100(3): 100907, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33518348

RESUMO

The objective of the present study was to determine the effect of monobutyrin supplementation on egg production, biochemical indexes, and gut microbiota of broiler breeders at the late stage of production. A total of 180 healthy Qingyuan partridge broilers were randomly assigned to 2 groups: 1) corn-soybean meal-based diet and 2) basal diet supplemented with 250 mg monobutyrin/kg. Each treatment group had 6 replicates/cages with 15 birds within each replicate. The experiment started at week 33 and lasted for 8 wk. Egg production rate, feed conversion rate, shell breaking strength, and shell thickness were not different between control and treatment groups. Supplementation of monobutyrin increased egg weight and tended to decrease egg breaking rate of Qingyuan partridge chickens. Supplementation of monobutyrin did not affect any of the biochemical indexes except total protein concentration. The 4 antioxidant parameters measured were not affected either. Alpha diversity indexes (Shannon, Simpson, Chao1, Ace, and Good's Coverage) and composition of cecal microbiota were not affected by monobutyrin supplementation. Overall, supplementation of monobutyrin at 250 mg/kg level improved egg quality, but its effect on cecal microbiota composition was limited.

16.
Poult Sci ; 100(2): 1034-1048, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518062

RESUMO

This study investigated the effect of berberine (BBR) on growth performance and composition and function of cecal microbiota in yellow-feathered broilers. A total of 360 1-day-old female broilers were assigned to 3 dietary treatments, each with 6 replicates of 20 birds. The dietary treatments consisted of a basal diet as negative control (NC), basal plus 200 mg/kg oxytetracycline calcium and 250 mg/kg nasiheptide as an antibiotic positive control (PC), and basal plus 250 mg/kg BBR. On day 21, 42, and 63, one chicken from each replicate was randomly selected for blood collection and cecal sampling. The 16S rRNA sequencing technology was used to analyze the community composition and function of cecal microbiota. Dietary supplementation with antibiotics or BBR increased the final body weight (BW) at day 63 and the average daily gain (ADG) during 1 to 21 d compared with the NC (P < 0.05). Supplementation with BBR improved the average daily feed intake (ADFI) at 22 to 42 d, 43 to 63 d, and 1 to 63 d (P < 0.05). Feed efficiency, indicated by feed to gain ratio (F/G), increased with PC during day 1 to 21 compared with NC (P < 0.05). The plasma concentrations of total protein at 42 d and uric acid at 21 d were increased, whereas creatine concentration at 63 d was decreased by BBR treatment (P < 0.05). The Chao 1 and Shannon index representing microbial α-diversity was reduced by BBR treatment (P < 0.05). The abundances of phylum Firmicutes and genera Lachnospiraceae, Lachnoclostridium, Clostridiales, and Intestinimonas were decreased, whereas the abundances of phylum Bacteroidetes and genus Bacteroides were increased with BBR treatment. Functional prediction of microbiota revealed that BBR treatment enriched pathways related to metabolism, organismal systems, and genetic information processing, especially DNA replication. The abundance of phylum Bacteroidetes, and genera Bacteroides and Lactobacillus in cecal contents were positively correlated with broiler growth performance. These results demonstrated dietary BBR supplementation improved the growth performance of yellow-feathered broilers, and was closely related to the significant changes in cecal microbiota composition.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33565856

RESUMO

Long-term stability of organic-inorganic hybrid perovskite solar cells (PSCs) is inhibited by ion diffusion. Herein, we introduce a thermally stable and hydrophobic silicone resin layer with a network structure as an interfacial layer between the perovskite and the hole-transporting layer (HTL). Experimental and theoretical investigations confirm that the small Si-O-Si unit in the network forms both Si-I and Pb-O bonds with the perovskite surface, which physically and chemically inhibit the diffusion and self-release of iodine. Besides, the silicone resin layer suppresses the thermal crystallization of spiro-OMeTAD and optimizes the interfacial energy level alignment for hole extraction. The power conversion efficiency (PCE) of a perovskite solar cell with a silicone resin layer is improved to 21.11%. The device maintains more than 90.1% of its original PCE after 1200 h under 85 °C thermal stress, 99.6% after 2000 h under RH ∼55 ± 5%, and 83% of its original PCE after light soaking in air for 1037 h.

18.
J Am Chem Soc ; 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33629850

RESUMO

Nanoporous materials are widely explored as efficient adsorbents for the storage of gases and liquids as well as for effective low-dielectric materials in large-scale integrated circuits. These applications require fast heat transfer, while most nanoporous substances are thermal insulators. Here, the oriented growth of micrometer-sized single-crystal covalent organic frameworks (COFs) ribbons with nanoporous structures at an air-water interface is presented. The obtained COFs ribbons are interconnected into a continuous and purely crystalline thin film. Due to the robust connectivity among the COFs ribbons, the entire film can be easily transferred and reliably contacted with target supports. The measured thermal conductivity amounts to ∼5.31 ± 0.37 W m-1 K-1 at 305 K, which is so far the highest value for nanoporous materials. These findings provide a methodology to grow and assemble single-crystal COFs into large area ensembles for the exploration of functional properties and potentially lead to new devices with COFs thin films where both porosity and thermal conductivity are desired.

19.
Acta Pharmacol Sin ; 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33633363

RESUMO

Immune checkpoint inhibition is an important strategy in cancer therapy. Blockade of CTLA-4 and PD-1/PD-L1 is well developed in clinical practice. In the last few years, LAG-3 has received much interest as an emerging novel target in immunotherapy. It was recently reported that FGL1 is a major ligand of LAG-3, which is normally secreted by the liver but is upregulated in several human cancers. FGL1 is a crucial biomarker and target for cancer immunotherapy. As the efficacy of immunotherapy is limited to specific types of patients, the subset of patients needs to be selected appropriately to receive precise treatment according to different biomarkers. To date, there is no test to accurately assess FGL1 expression levels. Nanobodies have some outstanding features, such as high stability, solubility and affinity for diagnostic and therapeutic applications. Here, we report the development and validation of a rapid, sensitive, and cost-effective nanobody-based immunoassay for the detection of FGL1 in human serum. In this study, human FGL1 recombinant protein was expressed and purified for the first time as an immunized antigen. Then, we constructed a nanobody phage display library and screened several nanobodies that bind FGL1 with high affinity. We selected two nanobodies targeting different epitopes of FGL1, one as a capture and the other conjugated with HRP as a probe. The double nanobody-based sandwich ELISA to detect the concentration of FGL1 showed a good response relationship in the range of 15.625-2000 ng/mL, and the recoveries from the spiked sample were in the range of 78% and 100%. This assay could be used as a potential approach for evaluating FGL1 expression for patient stratification and for predicting the therapeutic efficacy of targeting the LAG3/FGL1 axis.

20.
Mol Biol Rep ; 48(1): 677-689, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33442829

RESUMO

The vertebrate mitochondrial genome is typically circular molecules made up of 14,000 to 16,000 bp, including 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (12 s rRNA and 16 s rRNA) and a control region. Compared with nuclear DNA, mitochondrial DNA has a higher mutation rate, so it is one of the most effective and reliable molecular markers in fish phylogeny. Macrotocinclus affinis was the only species in Macrotocinclus (it was classified as Otocinclus in the past) and currently lacks genetic information. Most of the current researches are based on the mitochondrial Cytb gene and RAG1 and RAG2 nuclear genes to study the phylogenetic analysis of Siluriformes. So, the study provides the characteristic features of the Macrotocinclus affinis mitochondrial genome and this is the first time that the phylogenetic relationship of Siluriformes has been reconstructed based on COI. We aimed to sequence the entire mitochondrial genome of Macrotocinclus affinis using conventional PCR techniques and to clarify its phylogenetic status in Siluriformes by using the COI sequence of mitochondria. In this study, we sequenced the whole mitochondrial genome of this species yielding a 16,632 bp circular assembly composed of the typical vertebrate mitochondrial features. It contains 13 protein-coding genes, two rRNA genes, 22 tRNA genes, a putative control region, and one origin of replication on the light-strand. The overall base composition includes A (30.07%), T (24.43%), C (29.43%) and G (16.01%). The genome composition is A + T biased (54.5%), and exhibits AT-skew (0.1036) and GC-skew (-0.2962). Moreover, the 13 PCGs encode 3850 amino acids in total. The result of the phylogenetic tree supports Macrotocinclus affinis has a closest relationship with Otocinclus cf. hoppei far. These results will help to understand the characteristics of the mitochondrial genome of Macrotocinclus affinis and provide molecular basis for the evolutionary relationship of Loricariidae.

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