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1.
World J Clin Cases ; 12(7): 1339-1345, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38524509

RESUMO

BACKGROUND: Bradycardia-induced cardiomyopathy (BIC), which is a disease resulting from bradycardia, is characterized by cardiac chamber enlargement and diminished cardiac function. The correction of bradycardia can allow for significant improvements in both cardiac function and structure; however, this disease has been infrequently documented. In this case, we conducted a longitudinal follow-up of a patient who had been enduring BIC for more than 40 years to heighten awareness and prompt timely diagnosis and rational intervention. CASE SUMMARY: A woman who presented with postactivity fatigue and dyspnea was diagnosed with bradycardia at the age of 7. Since she had no obvious symptoms, she did not receive any treatment to improve her bradycardia during the 42-year follow-up, except for the implantation of a temporary pacemaker during labor induction surgery. As time progressed, the patient's heart gradually expanded due to her low ventricular rate, and she was diagnosed with BIC. In 2014, the patient developed atrial fibrillation, her ventricular rate gradually increased, and her heart shape gradually returned to normal. This report describes the cardiac morphological changes caused by the heart rate changes in BIC patients older than 40 years, introduces another possible outcome of BIC, and emphasizes the importance of early intervention in treating BIC. CONCLUSION: BIC can induce atrial fibrillation, causing an increased ventricular rate and leading to positive cardiac remodeling.

2.
Org Lett ; 26(8): 1595-1600, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38373166

RESUMO

Selective transformations at the more sterically hindered sites of organic molecules represent a frontier in the ability to precisely modify molecules. The lack of effective synthetic methods stands in stark contrast to the large number of encumbered sites encountered in molecules of interest. Here, we demonstrate that 1,2-bis(boronates) undergo selective alkynylation and alkenylation at the more sterically hindered C-B bond. Our preliminary mechanistic studies disclosed that this reaction can proceed through two convergent pathways involving direct coupling of sterically encumbered site versus 1,2-boron migratory coupling. Notably, this method facilitated convenient access to alkenyl and alkynyl boron products, which can be diversified by an array of transformations.

3.
Angew Chem Int Ed Engl ; 63(5): e202318441, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38098269

RESUMO

The construction of acyclic, non-adjacent 1,3-stereogenic centers, prevalent motifs in drugs and bioactive molecules, has been a long-standing synthetic challenge due to acyclic nucleophiles being distant from the chiral environment. In this study, we successfully synthesized highly valuable 1,2-bis(boronic) esters featuring acyclic and nonadjacent 1,3-stereocenters. Notably, this reaction selectively produces migratory coupling products rather than alternative deborylative allylation or direct allylation byproducts. This approach introduces a new activation mode for selective transformations of gem-diborylmethane in asymmetric catalysis. Additionally, we found that other gem-diborylalkanes, previously challenging due to steric hindrance, also successfully participated in this reaction. The incorporation of 1,2-bis(boryl)alkenes facilitated the diversification of the alkenyl and two boron moieties in our target compounds, thereby enabling access to a broad array of versatile molecules. DFT calculations were performed to elucidate the reaction mechanism and shed light on the factors responsible for the observed excellent enantioselectivity and diastereoselectivity. These were determined to arise from ligand-substrate steric repulsions in the syn-addition transition state.

4.
Angew Chem Int Ed Engl ; 62(48): e202312605, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37849448

RESUMO

1,3-Bis(boronic) esters can be readily synthesized from alkylBpin precursors. Selective transformations of these compounds hold the potential for late-stage functionalization of the remaining C-B bond, leading to a diverse array of molecules. Currently, there are no strategies available to address the reactivity and, more importantly, the controllable regiodivergent functionalization of 1,3-bis(boronic) esters. In this study, we have achieved controllable regiodivergent alkynylation of these molecules. The regioselectivity has been clarified based on the unique chelation patterns observed with different organometallic reagents. Remarkably, this methodology effectively addresses the low reactivity of 1,3-bis(boronic) esters and bridges the gap in radical chemistry, which typically yields only the classical products formed via stable radical intermediates. Furthermore, the compounds synthesized through this approach serve as potent building blocks for creating molecular diversity.

5.
Thorac Cancer ; 14(31): 3133-3139, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37718465

RESUMO

BACKGROUND: The aim of this study was to investigate the efficacy of bevacizumab (Bev) in reducing peritumoral brain edema (PTBE) after stereotactic radiotherapy (SRT) for lung cancer brain metastases. METHODS: A retrospective analysis was conducted on 44 patients with lung cancer brain metastases (70 lesions) who were admitted to our oncology and Gamma Knife center from January 2020 to May 2022. All patients received intracranial SRT and had PTBE. Based on treatment with Bev, patients were categorized as SRT + Bev and SRT groups. Follow-up head magnetic resonance imaging was performed to calculate PTBE and tumor volume changes. The edema index (EI) was used to assess the severity of PTBE. Additionally, the extent of tumor reduction and intracranial progression-free survival (PFS) were compared between the two groups. RESULTS: The SRT + Bev group showed a statistically significant difference in EI values before and after radiotherapy (p = 0.0115), with lower values observed after treatment, but there was no difference in the SRT group (p = 0.4008). There was a difference in the distribution of EI grades in the SRT + Bev group (p = 0.0186), with an increased proportion of patients at grades 1-2 after radiotherapy, while there was no difference in the SRT group (p > 0.9999). Both groups demonstrated a significant reduction in tumor volume after radiotherapy (p < 0.05), but there was no difference in tumor volume changes between the two groups (p = 0.4089). There was no difference in intracranial PFS between the two groups (p = 0.1541). CONCLUSION: Bevacizumab significantly reduces the severity of PTBE after radiotherapy for lung cancer. However, its impact on tumor volume reduction and intracranial PFS does not reach statistical significance.


Assuntos
Edema Encefálico , Neoplasias Encefálicas , Neoplasias Pulmonares , Radiocirurgia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/etiologia , Bevacizumab/farmacologia , Bevacizumab/uso terapêutico , Edema Encefálico/tratamento farmacológico , Edema Encefálico/etiologia , Edema Encefálico/patologia , Estudos Retrospectivos , Radiocirurgia/métodos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário
6.
Angew Chem Int Ed Engl ; 62(32): e202307447, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37316685

RESUMO

Asymmetric cross-couplings based on 1,2-carbon migration from B-ate complexes have been developed efficiently to access valuable organoboronates. However, enantioselective reactions triggered by 1,2-boron shift have remained to be unaddressed synthetic challenge. Here, Ir-catalyzed asymmetric allylic alkylation enabled by 1,2-boron shift was developed. In this reaction, we disclosed that excellent enantioselectivities were achieved through an interesting dynamic kinetic resolution (DKR) process of allylic carbonates at the elevated temperature. Notably, the highly valuable (bis-boryl)alkenes have enabled an array of diversifications to access versatile molecules. Extensive experimental and computational studies were conducted to elucidate the reaction mechanism of DKR process and clarify the origin of excellent enantioselectivities.

7.
Bioorg Chem ; 138: 106611, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37236073

RESUMO

Pseudo-natural products (PNPs) design strategy provides a great valuable entrance to effectively identify of novel bioactive scaffolds. In this report, novel pseudo-rutaecarpines were designed via the combination of several privileged structure units and 46 target compounds were synthesized. Most of them display moderate to potent inhibitory effect on LPS-induced NO production and low cytotoxicity in RAW264.7 macrophage. The results of the anti-inflammatory efficacy and action mechanism of compounds 7l and 8c indicated that they significantly reduced the release of IL-6, IL-1ß and TNF-α. Further studies revealed that they can strongly inhibit the activation of NF-κB and MAPK signal pathways. The LPS-induced acute liver injury mice model studies not only confirmed their anti-inflammatory efficacy in vivo but also could effectively relieve the liver injury in mice. The results suggest that compounds 7l and 8c might serve as lead compounds to develop therapeutic drugs for treatment of inflammation.


Assuntos
Lipopolissacarídeos , NF-kappa B , Animais , Camundongos , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Células RAW 264.7 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Fígado/metabolismo
8.
ACS Appl Mater Interfaces ; 15(17): 21066-21074, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37083353

RESUMO

Lithium (Li) metal is a promising anode for high-energy-density batteries; however, its practical viability is hampered by the unstable metal Li-electrolyte interface and Li dendrite growth. Herein, a mixed ion/electron conductive Li3N-Mo protective interphase with high mechanical stability is designed and demonstrated to stabilize the Li-electrolyte interface for a dendrite-free and ultrahigh-current-density metallic Li anode. The Li3N-Mo interphase is simultaneously formed and homogeneously distributed on the Li metal surface by the surface reaction between molten Li and MoN nanosheets powder. The highly ion-conductive Li3N and abundant Li3N/Mo grain boundaries facilitate fast Li-ion diffusion, while the electrochemically inert metal Mo cluster in the mosaic structure of Li3N-Mo inhibits the long-range crystallinity and regulates the Li-ion flux, further promoting the rate capability of the Li anode. The Li3N-Mo/Li electrode has a stable Li-electrolyte interface as manifested by a low Li overpotential of 12 mV and outstanding plating/stripping cyclability for over 3200 h at 1 mA cm-2. Moreover, the Li3N-Mo/Li anode inhibits Li dendrite formation and exhibits a long cycling life of 840 h even at 30 mA cm-2. The full cell assembled with LiFePO4 cathode exhibits stable cycling performance with 87.9% capacity retention for 200 cycles at 1C (1C = 170 mA g-1) as well as high rate capability of 83.7 mAh g-1 at 3C. The concept of constructing a mixed ion/electron conductive interphase to stabilize the Li-electrolyte interface for high-rate and dendrite-free Li metal anodes offers a viable strategy to develop high-performance Li-metal batteries.

9.
Acta Pharmacol Sin ; 44(8): 1549-1563, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37055533

RESUMO

Receptor-interacting protein kinase 1 (RIPK1) contributes to necroptosis. Our previous study showed that pharmacological or genetic inhibition of RIPK1 protects against ischemic stroke-induced astrocyte injury. In this study, we investigated the molecular mechanisms underlying RIPK1-mediated astrocyte injury in vitro and in vivo. Primary cultured astrocytes were transfected with lentiviruses and then subjected to oxygen and glucose deprivation (OGD). In a rat model of permanent middle cerebral artery occlusion (pMCAO), lentiviruses carrying shRNA targeting RIPK1 or shRNA targeting heat shock protein 70.1B (Hsp70.1B) were injected into the lateral ventricles 5 days before pMCAO was established. We showed that RIPK1 knockdown protected against OGD-induced astrocyte damage, blocked the OGD-mediated increase in lysosomal membrane permeability in astrocytes, and inhibited the pMCAO-induced increase in astrocyte lysosome numbers in the ischemic cerebral cortex; these results suggested that RIPK1 contributed to the lysosomal injury in ischemic astrocytes. We revealed that RIPK1 knockdown upregulated the protein levels of Hsp70.1B and increased the colocalization of Lamp1 and Hsp70.1B in ischemic astrocytes. Hsp70.1B knockdown exacerbated pMCAO-induced brain injury, decreased lysosomal membrane integrity and blocked the protective effects of the RIPK1-specific inhibitor necrostatin-1 on lysosomal membranes. On the other hand, RIPK1 knockdown further exacerbated the pMCAO- or OGD-induced decreases in the levels of Hsp90 and the binding of Hsp90 to heat shock transcription factor-1 (Hsf1) in the cytoplasm, and RIPK1 knockdown promoted the nuclear translocation of Hsf1 in ischemic astrocytes, resulting in increased Hsp70.1B mRNA expression. These results suggest that inhibition of RIPK1 protects ischemic astrocytes by stabilizing lysosomal membranes via the upregulation of lysosomal Hsp70.1B; the mechanism underlying these effects involves decreased Hsp90 protein levels, increased Hsf1 nuclear translocation and increased Hsp70.1B mRNA expression.


Assuntos
Astrócitos , Isquemia Encefálica , Ratos , Animais , Ratos Sprague-Dawley , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP70/farmacologia , Infarto da Artéria Cerebral Média/metabolismo , Lisossomos/metabolismo , RNA Interferente Pequeno/farmacologia , RNA Mensageiro/metabolismo , Glucose/metabolismo , Isquemia Encefálica/metabolismo
10.
Food Chem ; 418: 135986, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36996656

RESUMO

A simple and rapid method for in situ detection of aluminum in flour food was developed by using a self-made portable front face fluorescent system (PFFFS). The effects of pH, temperature, reaction time, protective agent and masking agent on the detection of Al3+ were investigated. The use of fluorescent probe protective agent, interfering ion masking agent, multi-point collection measurements and the working curves based on the analyte content in the real samples makes the present method have high accuracy, selectivity and reliability for in situ detection of Al3+ in flour foods. By comparison with the ICP-MS the accuracy and reliability of the present method were verified. The results showed that when 97 real samples were analyzed the Al3+ content values obtained by the present method and those obtained by ICP-MS method reached a highly significant correlation, with r ranging from 0.9747 to 0.9844. The self-made PFFFS combined with fluorescent probe does not require sample digestion, and can quickly detect Al3+ in flour food within 10 min. Therefore, the present method based on using FFFS has good practical application value for in-situ rapid detection of Al3+ in flour foods.


Assuntos
Farinha , Corantes Fluorescentes , Corantes Fluorescentes/química , Alumínio , Reprodutibilidade dos Testes
11.
Int J Biol Macromol ; 230: 123133, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36621733

RESUMO

Lytic polysaccharide monooxygenase (LPMO) is known as an oxidatively cleaving enzyme in recalcitrant polysaccharide deconstruction. Herein, we report a novel AA10 LPMO derived from Bacillus subtilis (BsLPMO10A). A substrate specificity study revealed that the enzyme exhibited an extensive active-substrate spectrum, particularly for polysaccharides linked via ß-1,4 glycosidic bonds, such as ß-(Man1 â†’ 4Man), ß-(Glc1 â†’ 4Glc) and ß-(Xyl1 â†’ 4Xyl). HPAEC-PAD and MALDI-TOF-MS analyses indicated that BsLPMO10A dominantly liberated native oligosaccharides with a degree of polymerization (DP) of 3-6 and C1-oxidized oligosaccharides ranging from DP3ox to DP6ox from mixed linkage glucans and beechwood xylan. Due to its synergistic action with a variety of glycoside hydrolases, including glucanase IDSGLUC5-38, xylanase TfXYN11-1, cellulase IDSGLUC5-11 and chitinase BtCHI18-1, BsLPMO10A dramatically accelerated glucan, xylan, cellulose and chitin saccharification. After co-reaction for 72 h, the reducing sugars in Icelandic moss lichenan, beechwood xylan, phosphoric acid swollen cellulose and chitin yielded 3176 ± 97, 7436 ± 165, 649 ± 44, and 2604 ± 130 µmol/L, which were 1.47-, 1.56-, 1.44- and 1.25-fold higher than those in the GHs alone groups, respectively (P < 0.001). In addition, the synergy of BsLPMO10A and GHs was further validated by the degradation of natural feedstuffs, the co-operation of BsLPMO10A and GHs released 3266 ± 182 and 1725 ± 107 µmol/L of reducing sugars from Oryza sativa L. and Arachis hypogaea L. straws, respectively, which were significantly higher than those produced by GHs alone (P < 0.001). Furthermore, BsLPMO10A also accelerated the liberation of reducing sugars from Celluclast® 1.5 L, a commercial cellulase cocktail, on filter paper, A. hypogaea L. and O. sativa L. straws by 49.58 % (P < 0.05), 72.19 % (P < 0.001) and 54.36 % (P < 0.05), respectively. This work has characterized BsLPMO10A with a broad active-substrate scope, providing a promising candidate for lignocellulosic biomass biorefinery.


Assuntos
Glicosídeos Cardíacos , Celulase , Xilanos/metabolismo , Bacillus subtilis/metabolismo , Glicosídeos , Polissacarídeos/metabolismo , Celulose/química , Oligossacarídeos/metabolismo , Oxigenases de Função Mista/química , Celulase/metabolismo , Quitina , Açúcares , Especificidade por Substrato
12.
Appl Microbiol Biotechnol ; 107(2-3): 677-689, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36572830

RESUMO

Pectate lyases (Pels) have a vital function in degradation of the primary plant cell wall and the middle lamella and have been widely used in the industry. In this study, two pectate lyase genes, IDSPel16 and IDSPel17, were cloned from a sheep rumen microbiome. The recombinant enzymes were expressed in Escherichia coli and functionally characterized. Both IDSPel16 and IDSPel17 proteins had an optimal temperature of 60 ℃, and an optimal pH of 10.0. IDSPel16 was relatively stable below 60 °C, maintaining 77.51% residual activity after preincubation at 60 °C for 1 h, whereas IDSPel17 denatured rapidly at 60 °C. IDSPel16 was relatively stable between pH 6.0 and 12.0, after pretreatment for 1 h, retaining over 60% residual activity. IDSPel16 had high activity towards polygalacturonic acid, with a Vmax of 942.90 ± 68.11, whereas IDSPel17 had a Vmax of only 28.19 ± 2.23 µmol/min/mg. Reaction product analyses revealed that IDSPel17 liberated unsaturated digalacturonate (uG2) and unsaturated trigalacturonate (uG3) from the substrate, indicating a typical endo-acting pectate lyase (EC 4.2.2.2). In contrast, IDSPel16 initially generated unsaturated oligogalacturonic acids, then converted these intermediates into uG2 and unsaturated galacturonic acid (uG1) as end products, a unique depolymerization profile among Pels. To the best of our knowledge, the IDSPel16 discovered with both endo-Pel (EC 4.2.2.2) and exo-Pel (EC 4.2.2.9) activities. These two pectate lyases, particularly the relatively thermo- and pH-stable IDSPel16, will be of interest for potential application in the textile, food, and feed industries. KEY POINTS: • Two novel pectate lyase genes, IDSPel16 and IDSPel17, were isolated and characterized from the sheep rumen microbiome. • Both IDSPel16 and IDSPel17 are alkaline pectate lyases, releasing unsaturated digalacturonate and unsaturated trigalacturonate from polygalacturonic acid. • IDSPel16, a bifunctional pectate lyase with endo-Pel (EC 4.2.2.2) and exo-Pel (EC 4.2.2.9) activities, could be a potential candidate for industrial application.


Assuntos
Polissacarídeo-Liases , Rúmen , Animais , Ovinos , Rúmen/metabolismo , Polissacarídeo-Liases/metabolismo , Clonagem Molecular
13.
Front Chem ; 10: 1074984, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465872

RESUMO

Rechargeable zinc-air batteries (ZABs) have gained a significant amount of attention as next-generation energy conversion and storage devices owing to their high energy density and environmental friendliness, as well as their safety and low cost. The performance of ZABs is dominated by oxygen electrocatalysis, which includes the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). Therefore, it is crucial to develop effective bifunctional oxygen electrocatalysts that are both highly active and stable. Carbon-based materials are regarded as reliable candidates because of their superior electrical conductivity, low price, and high durability. In this Review, we briefly introduce the configuration of ZABs and the reaction mechanism of bifunctional ORR/OER catalysts. Then, the most recent developments in carbon-based bifunctional catalysts are summarized in terms of carbon-based metal composites, carbon-based metal oxide composites, and other carbon-based composites. In the final section, we go through the significant obstacles and potential future developments for carbon-based bifunctional oxygen catalysts for ZABs.

14.
Front Chem ; 10: 907649, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651715

RESUMO

The catalytic hydrogenolysis of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF) is a promising route towards sustainable liquid fuels with a high energy density. Herein, a novel CuCoNiAl-containing mixed metal oxide catalyst (CuCoNiAl-MMO) was prepared by calcination a layered double hydroxide (LDH) precursor in N2 at 500 °C, then applied for the catalytic hydrogenolysis of HMF to DMF. The effects of reaction time, reaction temperature and hydrogen pressure on DMF selectivity were investigated. Under relatively mild reaction conditions (180°C, 1.0 MPa H2, 6.0 h), CuCoNiAl-MMO showed both a high initial activity and selectivity for hydrogenolysis of HMF to DMF, with HMF conversion rate of 99.8% and DMF selectivity of 95.3%. Catalysts characterization studies using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) revealed the presence of various metal oxides and metallic copper on the surface of the CuCoNiAl-MMO catalyst, with the presence of mixed metal-oxide-supported metallic Cu nanoparticles being responsible good hydrogenolysis activity of the catalyst for selective DMF synthesis.

15.
Front Psychol ; 13: 849847, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465554

RESUMO

Background: Neurobiological mechanisms underlying the recurrence of major depressive disorder (MDD) at different ages are unclear, and this study used the regional homogeneity (ReHo) index to compare whether there are differences between early onset recurrent depression (EORD) and late onset recurrent depression (LORD). Methods: Eighteen EORD patients, 18 LORD patients, 18 young healthy controls (HCs), and 18 older HCs were included in the rs-fMRI scans. ReHo observational metrics were used for image analysis and further correlation of differential brain regions with clinical symptoms was analyzed. Results: ANOVA analysis revealed significant differences between the four groups in ReHo values in the prefrontal, parietal, temporal lobes, and insula. Compared with EORD, the LORD had higher ReHo in the right fusiform gyrus/right middle temporal gyrus, left middle temporal gyrus/left angular gyrus, and right middle temporal gyrus/right angular gyrus, and lower ReHo in the right inferior frontal gyrus/right insula and left superior temporal gyrus/left insula. Compared with young HCs, the EORD had higher ReHo in the right inferior frontal gyrus/right insula, left superior temporal gyrus/left insula, and left rolandic operculum gyrus/left superior temporal gyrus, and lower ReHo in the left inferior parietal lobule, right inferior parietal lobule, and left middle temporal gyrus/left angular gyrus. Compared with old HCs, the LORD had higher ReHo in the right fusiform gyrus/right middle temporal gyrus, right middle temporal gyrus/right angular gyrus, and left rolandic operculum gyrus/left superior temporal gyrus, and lower ReHo in the right inferior frontal gyrus/right insula. ReHo in the right inferior frontal gyrus/right insula of patients with LORD was negatively correlated with the severity of 17-item Hamilton Rating Scale for Depression (HAMD-17) scores (r = -0.5778, p = 0.0120). Conclusion: Adult EORD and LORD patients of different ages have abnormal neuronal functional activity in some brain regions, with differences closely related to the default mode network (DMN) and the salience network (SN), and patients of each age group exhibit ReHo abnormalities relative to matched HCs. Clinical Trial Registration: [http://www.chictr.org.cn/], [ChiCTR1800014277].

16.
World J Microbiol Biotechnol ; 38(5): 87, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35397717

RESUMO

ß-Glucanases are a suite of glycoside hydrolases that depolymerize ß-glucan into cellooligosaccharides and/or monosaccharides and have been widely used as feed additives in livestock. In this study, two novel glucanase genes, IDSGluc5-26 and IDSGluc5-37, derived from sheep rumen microbiota, were expressed and functionally characterized. The optimal temperatures/pH of recombinant IDSGLUC5-26 and IDSGLUC5-37 were 50 °C/5.0 and 40 °C/6.0, respectively. Notably, IDSGLUC5-26 showed considerable stability under acidic conditions. Both IDSGLUC5-26 and IDSGLUC5-37 showed the highest activities toward barley ß-glucan, with Vmax values of 89.96 ± 9.19 µmol/min/mg and 459.50 ± 25.02 µmol/min/mg, respectively. Additionally, these two glucanases demonstrated hydrolysis of Icelandic moss lichenan and konjac gum, IDSGLUC5-26 releasing cellobiose (G2; occupying 17.37% of total reducing sugars), cellotriose (G3; 23.97%), and cellotetraose (G4; 30.93%) from barley ß-glucan and Icelandic moss lichenan after 10 min and suggestive of a typical endo-ß-1,4-glucanase (EC.3.2.1.4). In contrast, IDSGLUC5-37 was capable of liberating dominant G3 (64.11% or 67.55%) from barley ß-glucan or Icelandic moss lichenan, suggesting that the enzyme was likely an endo-ß-1,3 - 1,4-glucanases/lichenase (EC3.2.1.73). These findings describe the expression and characterization of two novel glucanase genes from sheep rumen microbiota. The two recombinant enzymes, particularly the acid-stable IDSGLUC5-26, will be of interest for potential application in food-/feed-additive development.


Assuntos
Microbiota , beta-Glucanas , Sequência de Aminoácidos , Animais , Glicosídeo Hidrolases/metabolismo , Proteínas Recombinantes/metabolismo , Rúmen , Ovinos , Especificidade por Substrato , beta-Glucanas/metabolismo
18.
Neurochem Res ; 47(5): 1329-1340, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35080688

RESUMO

The facial nerve is one of the vulnerable nerves in otolaryngology. Repair and recovery of facial nerve injury have a high priority in clinical practice. The proliferation and migration of Schwann cells are considered of great significance in the process of nerve injury repair. Danhong injection (DHI), as a common drug for cardiovascular and cerebrovascular diseases, has been fully certified in neuroprotection research, but its role in facial nerve injury is still not clear. Our study found that DHI can promote the proliferation and migration of RSC96 cells, a Schwann cell line, and this effect is related to the activation of the PI3K/AKT pathway. LY294002, an inhibitor of PI3K, inhibits the proliferation and migration of RSC96 cells. Further studies have found that DHI can also promote the expression of CXCL12 and GDNF at gene and protein levels, and CXCL12 is, while GDNF is not, PI3K/AKT pathway-dependent. Animal experiments also confirmed that DHI could promote CXCL12 and GDNF expression and promote facial nerve function recovery and myelin regeneration. In conclusion, our in vitro and in vivo experiments demonstrated that DHI could promote the proliferation and migration of Schwann cells through the PI3K/AKT pathway and increase the expression of CXCL12 and GDNF to promote facial nerve function repair.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Proliferação de Células , Medicamentos de Ervas Chinesas , Nervo Facial/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Regeneração Nervosa , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células de Schwann/metabolismo
19.
Patient Educ Couns ; 105(7): 1818-1827, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34952749

RESUMO

OBJECTIVE: To summarize the awareness levels of breast cancer (BC) worldwide and investigate factors associated with BC awareness to determine differences in awareness between China and other countries. METHODS: This systematic review followed the PRISMA guidelines and included 92 articles up to July, 2021. We calculated percentages for BC awareness levels and conducted subgroup analysis and cumulative meta-analysis. RESULTS: A total 84% (95% confidence interval [95%CI]: 78-90%) of women knew about BC; however, only 51% (95%CI: 37-66%) and 40% (95%CI: 24-56%) of women were aware of BC symptoms and BC risk factors, respectively. The most commonly known BC symptom was breast lump (71%, 95%CI: 62-80%), and BC family history was the most well-known BC risk factor (61%, 95%CI: 54-69%). Subgroup analysis showed lower awareness levels among Chinese and Asian women than women from other countries. Cumulative meta-analysis showed no obvious progress in BC awareness levels over time. We investigated 15 awareness-related factors, the most frequent of which were education level (61.8%), occupation (29.4%), and age (26.5%). CONCLUSION: BC awareness levels remain low. Improving BC awareness is critical, especially in developing countries. PRACTICE IMPLICATIONS: Effective education programs are urgently needed to improve women's BC awareness.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/diagnóstico , China , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos
20.
Carbohydr Polym ; 275: 118711, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742436

RESUMO

High amylose starch nanoparticles (HS-SNPs) were rapidly synthesised by high-speed circumferential force of homogenisation (3000 and 15,000 rpm) during nanoprecipitation. Morphology and dynamic light scattering analyses showed that HS-SNPs fabricated by stronger circumferential shearing were excellent stabilisers in smaller sizes (20-50 nm). Their aggregates were liable to separate in the aqueous phase with the nano effect under either homogenisation over 6 min or ultrasonication in 2 min. SNP-based nanoemulsion (<200 nm) of high-water fraction was achieved, though the high hydrophilicity of the SNPs were identified by the contact angle. For homogenisation (with 100-2000 nm emulsion size), only time prolongation led to a better dispersion of SNP aggregates. Ultrasonication with periodic cavitation could disintegrate SNP aggregates into micro-aggregates for a stable emulsion system in a short period. In contrast, long-term ultrasound caused simultaneous re-agglomeration and solubilisation of the SNPs, leading to weakened interface barriers and decreased storage stability.


Assuntos
Nanopartículas/química , Amido/química , Emulsões , Tamanho da Partícula , Estresse Mecânico
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