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1.
Drug Resist Updat ; 76: 101111, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38908233

RESUMEN

Gemcitabine (GEM) based induction chemotherapy is a standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). However, approximately 15 % of patients are still resistant to GEM-containing chemotherapy, which leads to treatment failure. Nevertheless, the underlying mechanisms of GEM resistance remain poorly understood. Herein, based on a microarray analysis, we identified 221 dysregulated lncRNAs, of which, DYNLRB2-AS1 was one of the most upregulated lncRNAs in GEM-resistance NPC cell lines. DYNLRB2-AS1 was shown to function as contain an oncogenic lncRNA that promoted NPC GEM resistance, cell proliferation, but inhibited cell apoptosis. Mechanistically, DYNLRB2-AS1 could directly bind to the DHX9 protein and prevent its interaction with the E3 ubiquitin ligase PRPF19, and thus blocking PRPF19-mediated DHX9 degradation, which ultimately facilitated the repair of DNA damage in the presence of GEM. Clinically, higher DYNLRB2-AS1 expression indicated an unfavourable overall survival of NPC patients who received induction chemotherapy. Overall, this study identified the oncogenic lncRNA DYNLRB2-AS1 as an independent prognostic biomarker for patients with locally advanced NPC and as a potential therapeutic target for overcoming GEM chemoresistance in NPC.

2.
J Biol Chem ; 299(7): 104873, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37257820

RESUMEN

Dysregulation of long noncoding RNAs (lncRNAs) contributes to tumorigenesis by modulating specific cancer-related pathways, but the roles of N6-methyladenosine (m6A)-enriched lncRNAs and underlying mechanisms remain elusive in nasopharyngeal carcinoma (NPC). Here, we reanalyzed the previous genome-wide analysis of lncRNA profiles in 18 pairs of NPC and normal tissues as well as in ten paired samples from NPC with or without post-treatment metastases. We discerned that an oncogenic m6A-enriched lncRNA, LINC00839, which was substantially upregulated in NPC and correlated with poor clinical prognosis, promoted NPC growth and metastasis both in vitro and in vivo. Mechanistically, by using RNA pull-down assay combined with mass spectrometry, we found that LINC00839 interacted directly with the transcription factor, TATA-box binding protein associated factor (TAF15). Besides, chromatin immunoprecipitation and dual-luciferase report assays demonstrated that LINC00839 coordinated the recruitment of TAF15 to the promoter region of amine oxidase copper-containing 1 (AOC1), which encodes a secreted glycoprotein playing vital roles in various cancers, thereby activating AOC1 transcription in trans. In this study, potential effects of AOC1 in NPC progression were first proposed. Moreover, ectopic expression of AOC1 partially rescued the inhibitory effect of downregulation of LINC00839 in NPC. Furthermore, we showed that silencing vir-like m6A methyltransferase-associated (VIRMA) and insulin-like growth factor 2 mRNA-binding proteins 1 (IGF2BP1) attenuated the expression level and RNA stability of LINC00839 in an m6A-dependent manner. Taken together, our study unveils a novel oncogenic VIRMA/IGF2BP1-LINC00839-TAF15-AOC1 axis and highlights the significance and prognostic value of LINC00839 expression in NPC carcinogenesis.


Asunto(s)
Neoplasias Nasofaríngeas , ARN Largo no Codificante , Factores Asociados con la Proteína de Unión a TATA , Humanos , Aminas , Carcinogénesis/genética , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/patología , Oxidorreductasas/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Factores Asociados con la Proteína de Unión a TATA/genética , Factores Asociados con la Proteína de Unión a TATA/metabolismo
3.
J Am Chem Soc ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953468

RESUMEN

Anthracenylidene is an intriguing structural unit with potential in various fields. The study presents a novel approach to introducing axial chirality into this all-carbon core skeleton through a remotely controlled desymmetrization strategy. A palladium-catalyzed enantioselective Heck arylation of exocyclic double bond of anthracene with two distinct substituents at the C10 position is harnessed to realize such a transformation. The judicious identification of the P-centrally chiral ligand is pivotal to ensure the competitive competence in reactivity and stereocontrol when the heteroatom handle is absent from the anthracenylidene skeleton. Both C10 mono- and disubstituted substrates were compatible for the established catalytic system, and structurally diverse anthracenylidene-based frameworks were forged with good-to-high enantiocontrol. The subsequent derivatization of the obtained products yielded a valuable array of centrally and axially chiral molecules, thus emphasizing the practicality of this chemistry. DFT calculations shed light on the catalytic mechanism and provided insights into the origin of the experimentally observed enantioselectivity for this reaction.

4.
Small ; : e2400630, 2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38431937

RESUMEN

Doxorubicin (DOX) is widely used as a chemotherapeutic agent for both hematologic and solid tumors and is a reasonable candidate for glioma treatment. However, its effectiveness is hindered by significant toxicity and drug resistance. Moreover, the presence of the blood-brain barrier (BBB) brings a crucial challenge to glioma therapy. In response, a GSH-responsive and actively targeted nanoprodrug delivery system (cRGD/PSDOX-Cur@NPs) are developed. In this system, a disulfide bond-bridged DOX prodrug (PEG-SS-DOX) is designed to release specifically in the high glutathione (GSH) tumor environment, markedly reducing the cardiotoxicity associated with DOX. To further address DOX resistance, curcumin, serving as a P-glycoprotein (P-gp) inhibitor, effectively increased cellular DOX concentration. Consequently, cRGD/PSDOX-Cur@NPs exhibited synergistic anti-tumor effects in vitro. Furthermore, in vivo experiments validated the superior BBB penetration and brain-targeting abilities of cRGD/PSDOX-Cur@NPs, showcasing the remarkable potential for treating both subcutaneous and orthotopic gliomas. This research underscores that this nanoprodrug delivery system presents a novel approach to inhibiting glioma while addressing resistance and systemic toxicity.

5.
J Transl Med ; 22(1): 572, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38880914

RESUMEN

BACKGROUND: Accurately identifying the risk level of drug combinations is of great significance in investigating the mechanisms of combination medication and adverse reactions. Most existing methods can only predict whether there is an interaction between two drugs, but cannot directly determine their accurate risk level. METHODS: In this study, we propose a multi-class drug combination risk prediction model named AERGCN-DDI, utilizing a relational graph convolutional network with a multi-head attention mechanism. Drug-drug interaction events with varying risk levels are modeled as a heterogeneous information graph. Attribute features of drug nodes and links are learned based on compound chemical structure information. Finally, the AERGCN-DDI model is proposed to predict drug combination risk level based on heterogenous graph neural network and multi-head attention modules. RESULTS: To evaluate the effectiveness of the proposed method, five-fold cross-validation and ablation study were conducted. Furthermore, we compared its predictive performance with baseline models and other state-of-the-art methods on two benchmark datasets. Empirical studies demonstrated the superior performances of AERGCN-DDI. CONCLUSIONS: AERGCN-DDI emerges as a valuable tool for predicting the risk levels of drug combinations, thereby aiding in clinical medication decision-making, mitigating severe drug side effects, and enhancing patient clinical prognosis.


Asunto(s)
Redes Neurales de la Computación , Humanos , Interacciones Farmacológicas , Combinación de Medicamentos , Medición de Riesgo , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Reproducibilidad de los Resultados , Gráficos por Computador
6.
Langmuir ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950193

RESUMEN

The key to enhancing water electrolysis efficiency lies in selecting highly efficient catalysts. Currently, high-entropy alloys (HEAs) are utilized in electrocatalysis applications owing to their diverse elemental composition, disordered elemental distribution, and the high solubility of each element, endowing them with excellent catalytic performance. The experiments were conducted using isoatomic FeNiCrMo HEA as a precursor, with a high-activity three-dimensional nanoporous structure rapidly synthesized via electrochemical one-step dealloying in a choline chloride-thiourea (ChCl-TU) deep eutectic solvent (DES). The results indicate that the dealloyed Fe20Co20Ni20Cr20Mo20 HEA mainly consists of two phases: face-centered cubic and σ phases. The imbalance in the distribution of elements in these two phases leads to quite different corrosion speeds with the FCC phase being preferentially corroded. Furthermore, synergistic electron coupling between surface atoms in the three-dimensional nanoporous structure strengthens the behavior of the oxygen evolution reaction (OER). At a current density of 40 mA cm-2, the overpotential after dealloying decreased to 370 mV, demonstrating excellent stability. The technique demonstrated in this work provides a novel approach to improve the catalytic activity of OER.

7.
Acta Pharmacol Sin ; 45(1): 166-179, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37605050

RESUMEN

Dry eye disease (DED) is a prevalent ocular disorder with a multifactorial etiology. The pre-angiogenic and pre-inflammatory milieu of the ocular surface plays a critical role in its pathogenesis. DZ2002 is a reversible type III S-adenosyl-L-homocysteine hydrolase (SAHH) inhibitor, which has shown excellent anti-inflammatory and immunosuppressive activities in vivo and in vitro. In this study, we evaluated the therapeutic potential of DZ2002 in rodent models of DED. SCOP-induced dry eye models were established in female rats and mice, while BAC-induced dry eye model was established in female rats. DZ2002 was administered as eye drops (0.25%, 1%) four times daily (20 µL per eye) for 7 or 14 consecutive days. We showed that topical application of DZ2002 concentration-dependently reduced corneal neovascularization and corneal opacity, as well as alleviated conjunctival irritation in both DED models. Furthermore, we observed that DZ2002 treatment decreased the expression of genes associated with angiogenesis and the levels of inflammation in the cornea and conjunctiva. Moreover, DZ2002 treatment in the BAC-induced DED model abolished the activation of the STAT3-PI3K-Akt-NF-κB pathways in corneal tissues. We also found that DZ2002 significantly inhibited the proliferation, migration, and tube formation of human umbilical endothelial cells (HUVECs) while downregulating the activation of the STAT3-PI3K-Akt-NF-κB pathway. These results suggest that DZ2002 exerts a therapeutic effect on corneal angiogenesis in DED, potentially by preventing the upregulation of the STAT3-PI3K-Akt-NF-κB pathways. Collectively, DZ2002 is a promising candidate for ophthalmic therapy, particularly in treating DED.


Asunto(s)
Neovascularización de la Córnea , Síndromes de Ojo Seco , Ratas , Humanos , Ratones , Animales , Femenino , Neovascularización de la Córnea/tratamiento farmacológico , Neovascularización de la Córnea/metabolismo , Neovascularización de la Córnea/patología , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Roedores/metabolismo , Células Endoteliales/metabolismo , Angiogénesis , Inflamación/tratamiento farmacológico , Síndromes de Ojo Seco/tratamiento farmacológico , Síndromes de Ojo Seco/inducido químicamente , Factor de Transcripción STAT3/metabolismo
8.
BMC Vet Res ; 20(1): 110, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500105

RESUMEN

BACKGROUND: Traumatic brain injury (TBI) is a common condition in veterinary medicine that is difficult to manage.Veterinary regenerative therapy based on adipose mesenchymal stem cells seem to be an effective strategy for the treatment of traumatic brain injury. In this study, we evaluated therapeutic efficacy of canine Adipose-derived mesenchymal stem cells (AD-MSCs)in a rat TBI model, in terms of improved nerve function and anti-neuroinflammation. RESULTS: Canine AD-MSCs promoted neural functional recovery, reduced neuronal apoptosis, and inhibited the activation of microglia and astrocytes in TBI rats. According to the results in vivo, we further investigated the regulatory mechanism of AD-MSCs on activated microglia by co-culture in vitro. Finally, we found that canine AD-MSCs promoted their polarization to the M2 phenotype, and inhibited their polarization to the M1 phenotype. What's more, AD-MSCs could reduce the migration, proliferation and Inflammatory cytokines of activated microglia, which is able to inhibit inflammation in the central system. CONCLUSIONS: Collectively, the present study demonstrates that transplantation of canine AD-MSCs can promote functional recovery in TBI rats via inhibition of neuronal apoptosis, glial cell activation and central system inflammation, thus providing a theoretical basis for canine AD-MSCs therapy for TBI in veterinary clinic.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Enfermedades de los Perros , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Enfermedades de los Roedores , Ratas , Animales , Perros , Lesiones Traumáticas del Encéfalo/terapia , Lesiones Traumáticas del Encéfalo/veterinaria , Microglía , Macrófagos , Inflamación/veterinaria , Trasplante de Células Madre Mesenquimatosas/veterinaria , Trasplante de Células Madre Mesenquimatosas/métodos
9.
Chem Biodivers ; 21(4): e202400256, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38361228

RESUMEN

The plant species, Sonchus wightianus DC., was historically used in China for both medicinal and dietary uses. In present study, seven new guaiane sesquiterpenoids (1-7) and one cytochalasin (8), along with five known guaianes (9-13) and two known cytochalasins (14 and 15), were isolated from the whole plants of S. wightianus. These guaianes showed structural variations in the substituents at C-8 and/or C-15, and compounds 6 and 7 are two sesquiterpenoid glycoside derivatives. Their structures were determined by extensive analysis of spectroscopic, electronic circular dichroism, and X-ray diffraction data, and chemical method. Biological tests revealed that compounds 5 and 8 are potent and selective immunosuppressive reagents.


Asunto(s)
Sesquiterpenos , Sonchus , Citocalasinas/química , Sesquiterpenos/farmacología , Sesquiterpenos/química , Difracción de Rayos X , China , Estructura Molecular
10.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38920362

RESUMEN

Twelve compounds, comprising of four new ones, 6ß,7α-limondiol (1) and ethyl 19-hydroxyisoobacunoate diosphenol (2), N-benzoyl 3-prenyltyramine (9) and 9-O-methyl integrifoliodiol (12), were isolated from the twigs with leaves of Tetradium trichotomum. The structures were elucidated by analysis of MS, NMR, and single-crystal X-ray diffraction. Compounds 1, 6, 8, 9 and 12 exhibited immunosuppressive activities in vitro against the proliferation of ConA-induced T lymphocytes and LPS-induced B cells.

11.
J Med Virol ; 95(1): e28281, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36329614

RESUMEN

Breast milk has been found to inhibit coronavirus infection, while the key components and mechanisms are unknown. We aimed to determine the components that contribute to the antiviral effects of breastmilk and explore their potential mechanism. Lactoferrin (Lf) and milk fat globule membrane inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related coronavirus GX_P2V and transcription- and replication-competent SARS-CoV-2 virus-like particles in vitro and block viral entry into cells. We confirmed that bovine Lf (bLf) blocked the binding between human angiotensin-converting enzyme 2 and SARS-CoV-2 spike protein by combining receptor-binding domain (RBD). Importantly, bLf inhibited RNA-dependent RNA polymerase (RdRp) activity of both SARS-CoV-2 and SARS-CoV in vitro in the nanomolar range. So far, no biological macromolecules have been reported to inhibit coronavirus RdRp. Our result indicated that bLf plays a major role in inhibiting viral replication. bLf treatment reduced viral load in lungs and tracheae and alleviated pathological damage. Our study provides evidence that bLf prevents SARS-CoV-2 infection by combining SARS-CoV-2 spike protein RBD and inhibiting coronaviruses' RdRp activity, and may be a promising candidate for the treatment of coronavirus disease 2019.


Asunto(s)
COVID-19 , SARS-CoV-2 , Femenino , Humanos , Cricetinae , SARS-CoV-2/metabolismo , Lactoferrina/farmacología , Lactoferrina/metabolismo , Glicoproteína de la Espiga del Coronavirus/metabolismo , Antivirales/farmacología , Antivirales/química , ARN Polimerasa Dependiente del ARN/metabolismo
12.
Connect Tissue Res ; 64(3): 274-284, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36537662

RESUMEN

AIM: Emerging data have demonstrated that low-grade inflammation in osteoarthritis, a long-held degenerative disease. The inflamed synovium produces various cytokines that induce cartilage destruction and joint pain. A previous study showed that teriparatide, an FDA approved anti-osteoporotic drug, may enhance cartilage repair. Our study focuses on its role in OA synovitis. MATERIALS AND METHODS: Primary mouse articular chondrocytes were used to determine the most potent cytokines involved in OA inflammation and cartilage destruction. A destabilization of the medial meniscus mouse model was established to investigate the effect of teriparatide in OA, particularly, on synovial inflammation and cartilage degradation. RESULTS: In vitro experiments showed that TNF-α was the most potent inducer of cartilage matrix-degrading enzymes, and that teriparatide antagonized the TNF-α of effect. Consistently, articular cartilage samples from TNF-α transgenic mice contained more MMP-13 positive chondrocytes than those from wild type mice. In addition, more type II collagen was cleaved in human OA cartilage than in normal cartilage samples. CONCLUSIONS: Teriparatide can prevent synovitis and cartilage degradation by suppressing TNF-α mediated MMP-13 overexpression. Together with its chondroregenerative capability, teriparatide may be the first effective disease modifying osteoarthritis drug.


Asunto(s)
Cartílago Articular , Osteoartritis , Sinovitis , Humanos , Ratones , Animales , Teriparatido/farmacología , Teriparatido/metabolismo , Metaloproteinasa 13 de la Matriz/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Cartílago/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Condrocitos/metabolismo , Osteoartritis/tratamiento farmacológico , Osteoartritis/metabolismo , Modelos Animales de Enfermedad , Sinovitis/tratamiento farmacológico , Ratones Transgénicos , Citocinas/metabolismo , Cartílago Articular/metabolismo
13.
J Org Chem ; 88(11): 6671-6681, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37220021

RESUMEN

Sulfoxides are ubiquitous in both naturally and synthetically bioactive molecules. We report herein a redox-neutral and mild approach for radical sulfinylation of redox-active esters via dual photoredox and copper catalysis, furnishing a series of functionalized sulfoxides. The reaction could accommodate a range of tertiary, secondary, and primary carboxylic acids, as well as exhibit wide functional group compatibility. The chemistry features a high degree of practicality, is scalable, and allows late-stage modification of bioactive pharmaceuticals.

14.
J Org Chem ; 88(1): 455-461, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36516399

RESUMEN

Baccaramiones A-D (1-4), four highly oxygenated and rearranged trinorditerpenoids, were isolated from Baccaurea ramiflora. Compound 1 is a 1(10 → 5)-abeo-15,16,17-trinor-ent-abietane featuring a unique 5/6/6 spirocyclic scaffold, and 2-4 are the first example of a novel 20(10 → 5)-abeo-15,16,17-trinor-ent-abietane skeleton. Their structures were established by spectroscopic analysis, X-ray crystallography, and electronic circular dichroism calculations. A plausible biosynthetic pathway for 1-4 was proposed. Interestingly, compounds 3 and 4 exhibited significant immunosuppressive activities against concanavalin A-induced T cell proliferation and lipopolysaccharide-induced B cell proliferation in vitro.


Asunto(s)
Abietanos , Inmunosupresores , Abietanos/química , Dicroismo Circular , Estructura Molecular
15.
BMC Cardiovasc Disord ; 23(1): 58, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36726083

RESUMEN

BACKGROUND/AIMS: The activation of the complement system and subsequent inflammatory responses are important features of myocardial ischemia/reperfusion (I/R) injury. Exosomes are nanoscale extracellular vesicles that play a significant role in remote ischemic preconditioning (RIPC) cardioprotection. The present study aimed to test whether RIPC-induced plasma exosomes (RIPC-Exo) exert protective effects on myocardial I/R injury by inhibiting complement activation and inflammation and whether exosomal heat shock protein 90 (HSP90) mediates these effects. METHODS: Rat hearts underwent 30 min of coronary ligation followed by 2 h of reperfusion. Plasma exosomes were isolated from RIPC rats and injected into the infarcted myocardium immediately after ligation. Sixty rats were randomly divided into Sham, I/R, I/R + RIPC-Exo (50 µg/µl), and RIPC-Exo + GA (geldanamycin, 1 mg/kg, administration 30 min before ligation) groups. Cardiomyocyte apoptosis, the release of myocardial markers (LDH, cTnI and CK-MB), infarct size, the expression of HSP90, complement component (C)3, C5a, c-Jun N-terminal kinase (JNK), interleukin (IL)-1ß, tumor necrosis factor (TNF)-alpha and intercellular adhesion molecule -1 (ICAM-1) were assessed. RESULTS: RIPC-Exo treatment significantly reduced I/R-induced cardiomyocyte apoptosis, the release of myocardial markers (LDH, cTnI and CK-MB) and infarct size. These beneficial effects were accompanied by decreased C3 and C5a expression, decreased inflammatory factor levels (IL-1ß, TNF-α, and ICAM-1), decreased JNK and Bax, and increased Bcl-2 expression. Meanwhile, the expression of HSP90 in the exosomes from rat plasma increased significantly after RIPC. However, treatment with HSP90 inhibitor GA significantly reversed the cardioprotection of RIPC-Exo, as well as activated complement component, JNK signalling and inflammation, indicating that HSP90 in exosomes isolated from the RIPC was important in mediating the cardioprotective effects during I/R. CONCLUSION: Exosomal HSP90 induced by RIPC played a significant role in cardioprotection against I/R injury, and its function was in part linked to the inhibition of the complement system, JNK signalling and local and systemic inflammation, ultimately alleviating I/R-induced myocardial injury and apoptosis by the upregulation of Bcl-2 expression and the downregulation of proapoptotic Bax.


Asunto(s)
Precondicionamiento Isquémico Miocárdico , Precondicionamiento Isquémico , Daño por Reperfusión Miocárdica , Ratas , Animales , Daño por Reperfusión Miocárdica/patología , Molécula 1 de Adhesión Intercelular , Proteína X Asociada a bcl-2 , Factor de Necrosis Tumoral alfa , Activación de Complemento , Inflamación , Infarto
16.
J Nat Prod ; 86(6): 1606-1614, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-37307145

RESUMEN

Chemical investigation of the twigs of Cleistanthus sumatranus (Phyllanthaceae) led to the isolation of 10 undescribed lignans, sumatranins A-J (1-10). Compounds 1-4 are unprecedented furopyran lignans characterized by a unique 2,3,3a,9a-tetrahydro-4H-furo[2,3-b]chromene heterotricyclic framework. Compounds 9 and 10 are rare 9'-nor-dibenzylbutane lignans. Structures were established based on analyses of spectroscopic data, X-ray crystallographic data, and experimental ECD spectra. Immunosuppressive assays revealed compounds 3 and 9 displayed moderate inhibitory effects with good selectivity indexes against LPS-induced B lymphocyte proliferation.


Asunto(s)
Lignanos , Malpighiales , Lignanos/farmacología , Lignanos/química , Estructura Molecular
17.
Anim Biotechnol ; 34(4): 1514-1523, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35167410

RESUMEN

The purpose of this study was to explore the effects of Rice straw and King grass on apparent digestibility, ruminal bacterial, and fungus composition in buffaloes. Three ruminal fistulated buffaloes were used in a 3 × 2 Latin square design. The dietary treatments were king grass and straw hay. Experimental animals were kept in individual pens and concentrate was offered at 1 kg/d while roughage was fed ad libitum. Each period lasted for 15d, with the first 12d for an adaptation period, followed by a 3-day formal trial period. King grass has higher digestibility of protein. Rice straw has higher digestibility to cellulose. The results showed that when buffaloes were fed king grass and straw, Bacteroidetes were dominant in the rumen normal flora, but firmicutes were not. In addition, the results of this experiment suggest that increasing protein content in diets may be beneficial to increase the relative abundance of Proteobacteria. Similarly, higher dietary fiber content may be beneficial for increasing relative abundance of Prevotella and Staphylococcus. The dominant fungi in ruminal fluid 2 h after ingestion were aerobic fungi. These aerobic fungi most likely entered the rumen with food. Whether and how long aerobic fungi can survive in the rumen needs more research.


Asunto(s)
Oryza , Poaceae , Animales , Búfalos/metabolismo , Alimentación Animal/análisis , Rumen/metabolismo , Dieta
18.
Diam Relat Mater ; 134: 109775, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36819598

RESUMEN

In this study, we introduced H-terminated diamond solution-gate field-effect transistor (H-diamond SGFET) to detect trace SARS-CoV-2 N-protein, which plays an important role in replication and transcription of viral RNA. 1-Pyrenebutyric acid-N-hydroxy succinimide ester (Pyr-NHS) was modified on H-diamond surface as linker, on which the specific antibody of SARS-CoV-2 N-protein was catenated. Fourier transform infrared spectrum, scanning electron microscope and energy dispersive spectrum were utilized to demonstrate the modification of H-diamond with Pyr-NHS and antibody. Shifts of IDS(max) at VGS = -500 mV in transfer characteristics of H-diamond SGFET was observed to determine N-protein concentration in phosphate buffer solution. Good linear relationship between IDS(max) and log10(N-protein) was observed from 10-14 to 10-5 g/mL with goodness of fit R2 = 0.90 and sensitivity of 1.98 µA/Log10 [concentration of N-protein] at VDS = -500 mV, VGS = -500 mV. Consequently, this prepared H-diamond SGFET biosensor may provide a new idea for diagnosis of SARS-CoV-2 due to a wide detection range from 10-14 to 10-5 g/mL and low limit of detection 10-14 g/mL.

19.
Angew Chem Int Ed Engl ; 62(1): e202213914, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36346195

RESUMEN

Anthrones and analogues are structural cores shared by diverse pharmacologically active natural and synthetic compounds. The sp2 -rich nature imposes inherent obstruction to introduce stereogenic element onto the tricyclic aromatic backbone. In our pursuit to expand the chemical space of axial chirality, a novel type of axially chiral anthrone-derived skeleton was discovered. This work establishes oxime ether as suitable functionality to furnish axial chirality on symmetric anthrone skeletons through stereoselective condensation of the carbonyl entity with long-range chirality control. The enantioenriched anthrones could be elaborated into dibenzo-fused seven-membered N-heterocycles containing well-defined stereogenic center via Beckmann rearrangement with axial-to-point chirality conversion.


Asunto(s)
Antracenos , Estereoisomerismo , Catálisis
20.
Small ; 18(25): e2201209, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35607794

RESUMEN

Emerging unfused-ring acceptors (UFAs) have been explored in pursuit of low-cost high-efficient organic solar cells (OSCs). Assembling unfused building blocks into proper frameworks are challenging for the molecular design of UFAs. The authors report herein four UFAs adopting either dithiophene cyclopentadiene (DTC) or dithieno[3,2-b:2',3'-d]pyrrole (DTP) as π-bridge units with different molecular frameworks for high-efficient as-cast OSCs. All these acceptors exhibit strong near-infrared absorption and narrow optical band gap (Eg opt  < 1.50 eV). DTC-bridged symmetric and DTP-bridged asymmetric UFAs exhibit higher planar conformation as well as suitable miscibility and homogeneous phase separation when blending with polymer donor PBDB-T to promote efficient charge transport in the blends. Their blends with PBDB-T contribute optimal PCE of 12.17% and 11.92% in as-cast OSCs, among the highest values for UFAs based as-cast devices in the literature. Experimental and theoretical simulations systematically reveal the impact of manipulating the molecular framework of UFAs on their conformation, optoelectronic, and photovoltaic performance. The results indicate the matching π-bridge units with molecular frameworks as an attractive approach to design UFAs for high-performance as-cast OSCs.

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