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1.
Water Sci Technol ; 89(10): 2839-2850, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38822618

RESUMO

Antibiotics release into the water environment through sewage discharge is a significant environmental concern. In the present study, we investigated the removal of ciprofloxacin (CIP) in simulated sewage by biological aeration filter (BAF) equipped with Fe3O4-modified zeolite (Fe3O4@ZF). Fe3O4@ZF were prepared with impregnation method, and the Fe3O4 particles were successfully deposited on the surface of ZF in an amorphous form according to the results of XPS and XRD analysis. The modification also increased the specific surface area (from 16.22 m²/g to 22 m²/g) and pore volume (from 0.0047 cm³/g to 0.0063 cm³/g), improving the adsorption efficiency of antibiotics. Fe3O4 modified ZF improved the treatment performance significantly, and the removal efficiency of CIP in BAF-Fe3O4@ZF was 79%±2.4%. At 10ml/L CIP, the BAF-Fe3O4@ZF reduced the relative abundances of antibiotics resistance genes (ARGs) int, mexA, qnrB and qnrS in the effluent by 57.16%, 39.59%, 60.22%, and 20.25%, respectively, which effectively mitigate the dissemination risk of ARGs. The modification of ZF increased CIP-degrading bacteria abundance, such as Rhizobium and Deinococcus-Thermus, and doubled bacterial ATP activity, promoting CIP degradation. This study offers a viable, efficient method to enhance antibiotic treatment and prevent leakage via sewage discharge.


Assuntos
Antibacterianos , Ciprofloxacina , Águas Residuárias , Poluentes Químicos da Água , Zeolitas , Zeolitas/química , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Águas Residuárias/química , Antibacterianos/farmacologia , Antibacterianos/química , Filtração/métodos , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodos , Adsorção , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Farmacorresistência Bacteriana/genética
2.
J Am Chem Soc ; 145(9): 5506-5511, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36790023

RESUMO

Given prominent physicochemical similarities between H2O2 and water, we report a new strategy for promoting the peroxygenase activity of P450 enzymes by engineering their water tunnels to facilitate H2O2 access to the heme center buried therein. Specifically, the H2O2-driven activities of two native NADH-dependent P450 enzymes (CYP199A4 and CYP153AM.aq) increase significantly (by >183-fold and >15-fold, respectively). Additionally, the amount of H2O2 required for an artificial P450 peroxygenase facilitated by a dual-functional small molecule to obtain the desired product is reduced by 95%-97.5% (with ∼95% coupling efficiency). Structural analysis suggests that mutating the residue at the bottleneck of the water tunnel may open a second pathway for H2O2 to flow to the heme center (in addition to the natural substrate tunnel). This study highlights a promising, generalizable strategy whereby P450 monooxygenases can be modified to adopt peroxygenase activity through H2O2 tunnel engineering, thus broadening the application scope of P450s in synthetic chemistry and synthetic biology.


Assuntos
Sistema Enzimático do Citocromo P-450 , Peróxido de Hidrogênio , Peróxido de Hidrogênio/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Heme/química
3.
Insect Mol Biol ; 32(2): 132-142, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36371609

RESUMO

Juvenile hormone (JH) controls almost every aspect of an insect, especially metamorphosis. Since RNA interference works on transcripts and is often insufficient in Lepidoptera, how JH affects larval development in these insects is not well studied. Using the CRISPR/Cas9 technique, we knocked out Spodoptera exigua methoprene-tolerant 1 (SeMet1) gene of beet armyworm by modifying two sites in the coding region. However, SeMet1 knockout did not affect egg hatch rate or larval development at L1-L3 stages. In contrast to the consistent five larval instars of the control group, L4 SeMet1 mutants began to show signs of precocious metamorphosis, that is, small patches of pupal cuticle. Most L4 and all L5 SeMet1 mutants died for failing to shed their mosaic cuticles. RNA-seq indicated that most genes encoding pupal cuticle proteins and chitinase genes were altered in SeMet1 mutant L4 larvae. SeKr-h1, a key transcription factor in JH action was significantly down-regulated in L3-L5 larvae, while SeBR-C, a pupal indicator was only upregulated in L4-L5 larvae. These results suggested that S. exigua larvae may initially develop independently of JH, and involve SeMet1 in transducing JH signalling, leading to controlled larval metamorphosis at the late larval stage. We believe our findings will enhance better understanding of JH regulation of larval development.


Assuntos
Beta vulgaris , Metoprene , Animais , Larva , Spodoptera/genética , Beta vulgaris/genética , Beta vulgaris/metabolismo , Sistemas CRISPR-Cas , Metamorfose Biológica , Hormônios Juvenis/metabolismo , Insetos/genética , Pupa , Proteínas de Insetos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
4.
Arch Insect Biochem Physiol ; 114(3): e22040, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37622407

RESUMO

CRISPR/Cas9 technology is a precise and powerful tool for functionally exploring insect genes. The present study tested CRISPR/Cas9 as a way of undertaking effective gene mutagenesis in an important agricultural pest, the beet armyworm Spodoptera exigua. Based on a S. exigua transcriptome database, the entire complementary DNA sequence of SeBLOS2 encoding 140 amino acid residues was cloned. The gene was highly expressed in late larval stages (L3-L5). Using the CRISPR/Cas9 method, SeBLOS2 was knocked out by altering two sites in the coding region. This resulted in 70%-74% of the G0 generation (L4-L5) larvae displaying mosaic translucent integument. Four different mutations occurred at SeBLOS2-specific target sites, as demonstrated by further polymerase chain reaction-based genotypic analysis. Homozygote mutant L3 larvae were obtained in the G1 generation, with complete loss of white stripes and spots on their larval integument. These results demonstrate a crucial role of SeBLOS2 in integument pigmentation and suggest that the gene can act as a suitable nonlethal marker for functional research on genes in S. exigua and other Lepidopteran pests.


Assuntos
Sistemas CRISPR-Cas , Tegumento Comum , Animais , Spodoptera/genética , Larva/genética , Genótipo
5.
Altern Ther Health Med ; 29(2): 90-96, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35139490

RESUMO

Context: Clinical-practice observations have revealed that novel coronavirus pneumonia is related to the dampness pathogen; most patients show a systemic inflammatory response syndrome (SIRS), and patients with a severe form of the disease have sepsis. Objective: The current study aimed to explore the role of Traditional Chinese medicine (TCM) and western medicine in the treatment of COVID-19. Design: The research team developed a case study. Setting: The study took place at the Nanchang Ninth Hospital in Nanchang, China. Participant: The participant was a 44-year-old female patient with diabetes who was a hepatitis B carrier. She was admitted to the hospital and diagnosed with novel coronavirus pneumonia at admission. Intervention: She was treated for seven days with Western medicine, at which time the nucleic acid test for the virus was negative; however, she still had flaky glass shadows in the lungs. She was then treated with TCM. Results: The patient reached the discharge standard on February 29. A recheck was performed on March 6, six days after discharge. Her chest CT showed that the two lung lesions continued to be absorbed, and the viral nucleic acid test was negative. Conclusions: For diagnosis and treatment of novel coronavirus pneumonia, the determination of the use of six channels or Wei-qi-Ying-blood differentiation needs to be combined with syndrome differentiation and to comply with the body's process of eliminating pathogens. The recovery of qi, blood and body fluid, and SIRS should be taken into account.


Assuntos
COVID-19 , Humanos , Feminino , Adulto , COVID-19/diagnóstico , Medicina Tradicional Chinesa , SARS-CoV-2 , Pulmão , Síndrome de Resposta Inflamatória Sistêmica , China , Teste para COVID-19
6.
Int J Mol Sci ; 24(22)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38003376

RESUMO

Bones serve mechanical and defensive functions, as well as regulating the balance of calcium ions and housing bone marrow.. The qualities of bones do not remain constant. Instead, they fluctuate throughout life, with functions increasing in some situations while deteriorating in others. The synchronization of osteoblast-mediated bone formation and osteoclast-mediated bone resorption is critical for maintaining bone mass and microstructure integrity in a steady state. This equilibrium, however, can be disrupted by a variety of bone pathologies. Excessive osteoclast differentiation can result in osteoporosis, Paget's disease, osteolytic bone metastases, and rheumatoid arthritis, all of which can adversely affect people's health. Osteoclast differentiation is regulated by transcription factors NFATc1, MITF, C/EBPα, PU.1, NF-κB, and c-Fos. The transcriptional activity of osteoclasts is largely influenced by developmental and environmental signals with the involvement of co-factors, RNAs, epigenetics, systemic factors, and the microenvironment. In this paper, we review these themes in regard to transcriptional regulation in osteoclastogenesis.


Assuntos
Reabsorção Óssea , Osteogênese , Humanos , Osteogênese/genética , Transdução de Sinais , Osteoclastos/metabolismo , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , NF-kappa B , Proteínas Proto-Oncogênicas c-fos/metabolismo , Fatores de Transcrição NFATC/genética , Diferenciação Celular/genética , Ligante RANK
7.
Molecules ; 28(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36677642

RESUMO

As aging progresses, ß-amyloid (Aß) deposition and the resulting oxidative damage are key causes of aging diseases such as senior osteoporosis (SOP). Humulus lupulus L. (hops) is an important medicinal plant widely used in the food, beverage and pharmaceutical industries due to its strong antioxidant ability. In this study, APP/PS1 mutated transgenic mice and Aß-injured osteoblasts were used to evaluate the protective effects of hops extracts (HLE) on SOP. Mice learning and memory levels were assessed by the Morris water maze. Mice femurs were prepared for bone micro-structures and immunohistochemistry experiments. The deposition of Aß in the hippocampus, cortex and femurs were determined by Congo red staining. Moreover, protein expressions related to antioxidant pathways were evaluated by Western blotting. It was found that HLE markedly improved learning abilities and ameliorated memory impairment of APP/PS1 mice, as well as regulated antioxidant enzymes and bone metabolism proteins in mice serum. Micro-CT tests indicated that HLE enhanced BMD and improved micro-architectural parameters of mice femur. More importantly, it was discovered that HLE significantly reduced Aß deposition both in the brain and femur. Further in vitro results showed HLE increased the bone mineralization nodule and reduced the ROS level of Aß-injured osteoblasts. Additionally, HLE increased the expression of antioxidant related proteins Nrf2, HO-1, NQO1, FoxO1 and SOD-2. These results indicated that Humulus lupulus L. extract could protect against senior osteoporosis through inhibiting Aß deposition and oxidative stress, which provides a reference for the clinical application of hops in the prevention and treatment of SOP.


Assuntos
Doença de Alzheimer , Humulus , Osteoporose , Extratos Vegetais , Animais , Camundongos , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Antioxidantes/metabolismo , Modelos Animais de Doenças , Humulus/química , Camundongos Transgênicos , Osteoblastos/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Estresse Oxidativo , Presenilina-1/genética , Presenilina-1/metabolismo , Extratos Vegetais/farmacologia
8.
Angew Chem Int Ed Engl ; 62(51): e202311259, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37713467

RESUMO

A recent novel strategy for constructing artificial metalloenzymes (ArMs) that target new-to-nature functions uses dual-functional small molecules (DFSMs) with catalytic and anchoring groups for converting P450BM3 monooxygenase into a peroxygenase. However, this process requires excess DFSMs (1000 equivalent of P450) owing to their low binding affinity for P450, thus severely limiting its practical application. Herein, structural optimization of the DFSM-anchoring group considerably enhanced their binding affinity by three orders of magnitude (Kd ≈10-8  M), thus approximating native cofactors, such as FMN or FAD in flavoenzymes. An artificial cofactor-driven peroxygenase was thus constructed. The co-crystal structure of P450BM3 bound to a DFSM clearly revealed a precatalytic state in which the DFSM participates in H2 O2 activation, thus facilitating peroxygenase activity. Moreover, the increased binding affinity substantially decreases the DFSM load to as low as 2 equivalents of P450, while maintaining increased activity. Furthermore, replacement of catalytic groups showed disparate selectivity and activity for various substrates. This study provides an unprecedented approach for assembling ArMs by binding editable organic cofactors as a co-catalytic center, thereby increasing the catalytic promiscuity of P450 enzymes.


Assuntos
Sistema Enzimático do Citocromo P-450 , Metaloproteínas , Sistema Enzimático do Citocromo P-450/metabolismo , Catálise , Metaloproteínas/química
9.
Angew Chem Int Ed Engl ; 62(4): e202215088, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36417593

RESUMO

It is a great challenge to optionally access diverse hydroxylation products from a given substrate bearing multiple reaction sites of sp3 and sp2 C-H bonds. Herein, we report the highly selective divergent hydroxylation of alkylbenzenes by an engineered P450 peroxygenase driven by a dual-functional small molecule (DFSM). Using combinations of various P450BM3 variants with DFSMs enabled access to more than half of all possible hydroxylated products from each substrate with excellent regioselectivity (up to >99 %), enantioselectivity (up to >99 % ee), and high total turnover numbers (up to 80963). Crystal structure analysis, molecular dynamic simulations, and theoretical calculations revealed that synergistic effects between exogenous DFSMs and the protein environment controlled regio- and enantioselectivity. This work has implications for exogenous-molecule-modulated enzymatic regiodivergent and enantioselective hydroxylation with potential applications in synthetic chemistry.


Assuntos
Simulação de Dinâmica Molecular , Engenharia de Proteínas , Hidroxilação , Estereoisomerismo , Domínio Catalítico , Especificidade por Substrato
10.
Angew Chem Int Ed Engl ; 62(13): e202217678, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36660956

RESUMO

Applications of the peroxidase activity of cytochrome P450 enzymes in synthetic chemistry remain largely unexplored. We present herein a protein engineering strategy to increase cytochrome P450BM3 peroxidase activity for the direct nitration of aromatic compounds and terminal aryl-substituted olefins in the presence of a dual-functional small molecule (DFSM). Site-directed mutations of key active-site residues allowed the efficient regulation of steric effects to limit substrate access and, thus, a significant decrease in monooxygenation activity and increase in peroxidase activity. Nitration of several phenol and aniline compounds also yielded ortho- and para-nitration products with moderate-to-high total turnover numbers. Besides direct aromatic nitration by P450 variants using nitrite as a nitrating agent, we also demonstrated the use of the DFSM-facilitated P450 peroxidase system for the nitration of the vinyl group of styrene and its derivatives.


Assuntos
Sistema Enzimático do Citocromo P-450 , Hidrocarbonetos , Sistema Enzimático do Citocromo P-450/metabolismo , Compostos Orgânicos , Fenóis/química , Peroxidases
11.
Biopharm Drug Dispos ; 43(1): 11-22, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34914109

RESUMO

Xanthohumol, a natural isoflavone from Humulus lupulus L., possesses biological activities. However, the biological fate of xanthohumol in vivo remains unclear. The aim of this study was to investigate the absorption and metabolism of xanthohumol in rats through UPLC-MS/MS. The plasma, urine and fecal samples were collected after oral administration of xanthohumol (25, 50, 100 mg/kg) in SD rats. The contents of xanthohumol and its metabolites were determined by UPLC-MS/MS. A total of 6 metabolites of xanthohumol were identified in rats, including methylated, glucuronidated, acid-catalyzed cyclization and oxidation, indicating xanthohumol underwent phase I and II metabolism. Besides, isoxanthohumol was the major metabolites of xanthohumol. Xanthohumol was rapidly absorbed, metabolized, and eliminated in rats. The pharmacokinetics results showed the Tmax of xanthohumol and isoxanthohumol were 3 and 2.33 h, respectively. The AUC0-t of xanthohumol and isoxanthohumol were 138.83 ± 6.03 and 38.77 ± 4.46 ng/ml·h, respectively. Furthermore, xanthohumol was mainly excreted in the form of prototype through feces and a small amount of xanthohumol was excreted through urine. These results illustrated the absorption, metabolism, and pharmacokinetics process of xanthohumol in rats, and provided a reference for the further rational applications.


Assuntos
Flavonoides , Propiofenonas , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Flavonoides/metabolismo , Flavonoides/farmacocinética , Propiofenonas/metabolismo , Propiofenonas/farmacocinética , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
12.
Sensors (Basel) ; 22(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36560166

RESUMO

Integrity monitoring (IM) is essential if GNSS positioning technologies are to be fully trusted by future intelligent transport systems. A tighter and conservative stochastic model can shrink protection levels in the position domain and therefore enhance the user-level integrity. In this study, the stochastic models for vehicle-based GNSS positioning are refined in three respects: (1) Gaussian bounds of precise orbit and clock error products from the International GNSS Service are used; (2) a variable standard deviation to characterize the residual tropospheric delay after model correction is adopted; and (3) an elevation-dependent model describing the receiver-related errors is adaptively refined using least-squares variance component estimation. The refined stochastic models are used for positioning and IM under the Advanced Receiver Autonomous Integrity Monitoring (ARAIM) framework, which is considered the basis for multi-constellation GNSS navigation to support air navigation in the future. These refinements are assessed via global simulations and real data experiments. Different schemes are designed and tested to evaluate the corresponding enhancements on ARAIM availability for both aviation and ground vehicle-based positioning applications.

13.
Int J Mol Sci ; 23(14)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35887253

RESUMO

We recently developed an artificial P450-H2O2 system assisted by dual-functional small molecules (DFSMs) to modify the P450BM3 monooxygenase into its peroxygenase mode, which could be widely used for the oxidation of non-native substrates. Aiming to further improve the DFSM-facilitated P450-H2O2 system, a series of novel DFSMs having various unnatural amino acid groups was designed and synthesized, based on the co-crystal structure of P450BM3 and a typical DFSM, N-(ω-imidazolyl)-hexanoyl-L-phenylalanine, in this study. The size and hydrophobicity of the amino acid residue in the DFSM drastically affected the catalytic activity (up to 5-fold), stereoselectivity, and regioselectivity of the epoxidation and hydroxylation reactions. Docking simulations illustrated that the differential catalytic ability among the DFSMs is closely related to the binding affinity and the distance between the catalytic group and heme iron. This study not only enriches the DFSM toolbox to provide more options for utilizing the peroxide-shunt pathway of cytochrome P450BM3, but also sheds light on the great potential of the DFSM-driven P450 peroxygenase system in catalytic applications based on DFSM tunability.


Assuntos
Sistema Enzimático do Citocromo P-450 , Peróxido de Hidrogênio , Aminoácidos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Peróxido de Hidrogênio/metabolismo , Hidroxilação , Oxigenases de Função Mista
14.
J Integr Neurosci ; 20(2): 375-383, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34258936

RESUMO

This research investigates the characteristics of spontaneous brain activity in dysthyroid optic neuropathy patients using the regional homogeneity technique. Sixteen patients with dysthyroid optic neuropathy and 16 thyroid-associated ophthalmopathy patients without dysthyroid optic neuropathy were recruited, matched for weight, height, age, sex, and educational level. All participants underwent resting-state functional nuclear resonance imaging, and the characteristics of spontaneous brain activity were evaluated using the regional homogeneity technique. Each participant in the dysthyroid optic neuropathy group also completed the Hospital Anxiety and Depression scale. Receiver operating characteristic curves were used to compare brain activity between the two groups. Pearson correlation analysis evaluated the relationship between regional homogeneity and clinical manifestations in dysthyroid optic neuropathy patients. In addition, we analyzed the correlation between Hospital Anxiety and Depression scale and regional homogeneity. We found that the regional homogeneity values at the corpus callosum/cingulate gyrus and parietal lobe/middle frontal gyrus significantly decreased in dysthyroid optic neuropathy patients. Regional homogeneity values at the corpus callosum/cingulate gyrus and parietal lobe/middle frontal gyrus were negatively correlated with Hospital Anxiety and Depression scale and disease duration. It was found that the regional homogeneity signal values were significantly lower than in thyroid-associated ophthalmopathy without in dysthyroid optic neuropathy, which may indicate a risk of regional brain dysfunction in dysthyroid optic neuropathy. The results show that regional homogeneity has the potential for early diagnosis and prevent dysthyroid optic neuropathy. In addition, the findings suggest possible mechanisms of dysthyroid optic neuropathy optic nerve injury. They may provide a valuable basis for further research on the pathological mechanisms of dysthyroid optic neuropathy.


Assuntos
Córtex Cerebral/fisiopatologia , Conectoma , Corpo Caloso/fisiopatologia , Oftalmopatia de Graves/fisiopatologia , Rede Nervosa/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Corpo Caloso/diagnóstico por imagem , Feminino , Oftalmopatia de Graves/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Doenças do Nervo Óptico/diagnóstico por imagem
15.
J Integr Neurosci ; 20(4): 885-893, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34997712

RESUMO

The spontaneous changes in brain activity in patients with diabetic optic neuropathy using steady-state fMRI. The fractional amplitude of the low-frequency fluctuation method was applied to evaluate neural activity changes. The Hospital Anxiety and Depression Scale was used to assess the anxiety and depression status of participants. The independent sample t-test and chi-squared test were applied to analyze the demographics of diabetic optic neuropathy patients and healthy controls. Receiver operating characteristic curves were applied to analyze the variation in mean fractional amplitude of low-frequency fluctuation values between diabetic optic neuropathy patients and healthy controls. Pearson's correlation analysis analyzed the relationships between the fractional amplitude of low-frequency fluctuation values of brain regions and clinical behaviors in the diabetic optic neuropathy group. The fractional amplitude of low-frequency fluctuation value of diabetic optic neuropathy patients was significantly higher than healthy controls in the right precentral gyrus. However, the fractional amplitude of low-frequency fluctuation values in the right anterior cingulate gyrus and left middle cingulate gyrus were markedly decreased in diabetic optic neuropathy patients. The area under the curve of receiver operating characteristics for each brain region showed high accuracy. Pearson's correlation analysis showed that fractional amplitude of low-frequency fluctuation values of the right anterior cingulate gyrus and left middle cingulate gyrus was negatively correlated with Hospital Anxiety and Depression Scale scores. The fractional amplitude of low-frequency fluctuation values of the left middle cingulate gyrus was negatively correlated with diabetic optic neuropathy disease duration. In conclusion, we found abnormal spontaneous brain activities in regions related to cognitive and emotional dysfunction, eye movement disorder, and vision loss in patients with diabetic optic neuropathy. These results may indicate the underlying neuropathological mechanisms of diabetic optic neuropathy and show that fractional amplitude of low-frequency fluctuation may be an effective method to distinguish patients with diabetic optic neuropathy from healthy individuals.


Assuntos
Neuropatias Diabéticas/fisiopatologia , Neuroimagem Funcional , Giro do Cíngulo/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Neuropatias Diabéticas/diagnóstico por imagem , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças do Nervo Óptico/diagnóstico por imagem
16.
Chembiochem ; 21(14): 2019-2028, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32180316

RESUMO

Phosphate: acyl-acyl carrier protein (ACP) acyltransferase PlsX is a peripheral enzyme catalysing acyl transfer to orthophosphate in phospholipid synthesis. Little is known about how it recognises substrates and catalyses the acyl transfer. Here we show that its active site includes many residues lining a long, narrow gorge at the dimeric interface, two positive residues forming a positive ACP docking pad next to the interfacial gorge, and a number of strictly conserved residues significantly contributing to the catalytic activity. These findings suggest a substrate recognition mode and a catalytic mechanism that are different from those of phosphotransacetylases catalysing a similar acyl transfer reaction. The catalytic mechanism involves substrate activation and transition-state stabilization by two strictly conserved residues, Lys184 and Asn229. Another noticeable feature of the catalysis is the release of the acyl phosphate product near the membrane, which might facilitate its membrane insertion.


Assuntos
Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , Biocatálise , Domínio Catalítico , Fosfolipídeos/biossíntese , Especificidade por Substrato
17.
J Transl Med ; 17(1): 117, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30961629

RESUMO

BACKGROUND: Extrahepatic metastasis is the independent risk factor of poor survival of primary hepatic carcinoma (PHC), and most occurs in the chest and abdomen. Currently, there is still no available method to predict thoracoabdominal extrahepatic metastasis in PHC. In this study, a novel nomogram model was developed and validated for prediction of thoracoabdominal extrahepatic metastasis in PHC, thereby conducted individualized risk management for pretreatment different risk population. METHODS: The nomogram model was developed in a primary study that consisted of 330 consecutive pretreatment patients with PHC. Large-scale datasets were extracted from clinical practice. The nomogram was based on the predictors optimized by data dimension reduction through Lasso regression. The prediction performance was measured by the area under the receiver operating characteristic (AUROC), and calibrated to decrease the overfit bias. Individualized risk management was conducted by weighing the net benefit of different risk population via decision curve analysis. The prediction performance was internally and independently validated, respectively. An independent-validation study using a separate set of 107 consecutive patients. RESULTS: Four predictors from 55 high-dimensional clinical datasets, including size, portal vein tumor thrombus, infection, and carbohydrate antigen 125, were incorporated to develop a nomogram model. The nomogram demonstrated valuable prediction performance with AUROC of 0.830 (0.803 in internal-validation, and 0.773 in independent-validation, respectively), and fine calibration. Individual risk probability was visually scored. Weighing the net benefit, threshold probability was classified for three-independent risk population, which was < 19.9%, 19.9-71.8% and > 71.8%, respectively. According to this classification, pretreatment risk management was based on a treatment-flowchart for individualized clinical decision-making. CONCLUSIONS: The proposed nomogram is a useful tool for pretreatment risk management of thoracoabdominal extrahepatic metastasis in PHC for the first time, and may handily facilitate timely individualized clinical decision-making for different risk population.


Assuntos
Neoplasias Hepáticas/patologia , Modelos Biológicos , Nomogramas , Gestão de Riscos , Algoritmos , Calibragem , Tomada de Decisão Clínica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Curva ROC , Fatores de Risco
18.
Arch Insect Biochem Physiol ; 101(3): e21554, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31033012

RESUMO

Acetylcholinesterase (AChE) is a vital enzyme that hydrolyzes acetylcholine. Here, full-length complementary DNAs (cDNAs) of two acetylcholinesterase genes (SeAce1 and SeAce2) were obtained from Spodoptera exigua, a widespread phytophagous pest in agriculture. The complete SeAce1 cDNA comprised 5447 nucleotides including an open reading frame (ORF) encoding 694 amino acids, while SeAce2 cDNA encompassed a 1917-bp ORF which would likely yield 638 amino acids. Both SeAce1 and SeAce2 contained specific characteristics of functional AChE. A phylogenetic tree of all lepidopteran insect Aces showed S. exigua clustered with S. litura, Helicoverpa assulta, and H. armigera, all of which are Noctuidae. In S. exigua, SeAce1 gene expression levels (reverse transcription polymerase chain reaction [RT-PCR] and quantitative RT-PCR) were markedly increased compared with SeAce2 in all developmental phases and tissue types. Both genes were down regulated by inserting the corresponding dsRNAs in 5th instar larvae, which resulted in 56.7% (SeAce1) and 24.6% (SeAce2) death. Downregulation of both SeAce1 and SeAce2 significantly reduced fecundity and vitellogenin gene expression in S. exigua. These results revealed the biological functions of the two Ace genes (SeAce1 and SeAce2), providing novel insights into the development of strategies for controlling insect pests.


Assuntos
Acetilcolinesterase/genética , Proteínas de Insetos/genética , Spodoptera/genética , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Sequência de Aminoácidos , Animais , Regulação para Baixo , Expressão Gênica , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Filogenia , Alinhamento de Sequência , Spodoptera/enzimologia
19.
Molecules ; 24(2)2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-30641909

RESUMO

Rehmanniae Radix Preparata (RR), the dry rhizome of Rehmannia glutinosa Libosch., is a traditional herbal medicine for improving the liver and kidney function. Ample clinical and pharmacological experiments show that RR can prevent post-menopausal osteoporosis and senile osteoporosis. In the present study, in vivo and in vitro experiments, as well as a UHPLC-Q/TOF-MS-based metabolomics study, were used to explore the preventing effect of RR on glucocorticoid-induced osteoporosis (GIOP) and its underlying mechanisms. As a result, RR significantly enhanced bone mineral density (BMD), improved the micro-architecture of trabecular bone, and intervened in biochemical markers of bone metabolism in dexamethasone (DEX)-treated rats. For the in vitro experiment, RR increased the cell proliferation and alkaline phosphatase (ALP) activity, enhanced the extracellular matrix mineralization level, and improved the expression of runt-related transcription factor 2 (RUNX2) and osteopontin (OPN) in DEX-injured osteoblasts. For the metabolomics study, a total of 27 differential metabolites were detected in the DEX group vs. the control group, of which 10 were significantly reversed after RR treatment. These metabolites were majorly involved in steroid hormone biosynthesis, sex steroids regulation, and amino acid metabolism. By metabolic pathway and Western blotting analysis, it was further ascertained that RR protected against DEX-induced bone loss, mainly via interfering steroid hormone biosynthesis, as evidenced by the up-regulation of cytochrome P450 17A1 (CYP17A1) and aromatase (CYP19A1), and the down-regulation of 11ß-hydroxysteroid dehydrogenase (HSD11B1). Collectively, these results indicated that RR had a notable preventing effect on GIOP, and the action mechanism might be related to steroid hormone biosynthesis.


Assuntos
Hormônios/biossíntese , Metaboloma , Metabolômica , Osteoporose/etiologia , Osteoporose/metabolismo , Extratos Vegetais/farmacologia , Rehmannia/química , Esteroides/biossíntese , Animais , Biomarcadores , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Glucocorticoides/efeitos adversos , Espectrometria de Massas , Metabolômica/métodos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoporose/patologia , Extratos Vegetais/química , Ratos
20.
Bioorg Med Chem Lett ; 28(4): 626-629, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29395979

RESUMO

A new tricoumarin glycoside, triumbelletin-7-O-ß-d-glucoside (1) and a new biflavonoid, wikstroflavone A (2), together with two known compounds, wikstaiwanone A (3) and wikstaiwanone B (4), were isolated from the rhizome of Wikstroemia indica. The structures of new compounds were elucidated by extensive spectroscopic techniques (UV, IR, HRESIMS, 1D, 2D NMR and CD), in combination with quantum chemical calculations of 13C NMR and ECD spectra. All isolates were tested for their antineoplastic activities against cancer-derived cell lines HCT116, SW480, U87 and T98G. Compounds 2-4 exhibited moderate cytotoxic activities to the four cell lines. The flow cytometry assay and western blot analysis revealed that the cytotoxic effects were possibly attributed to the induced apoptotic cell death.


Assuntos
Antineoplásicos/farmacologia , Biflavonoides/farmacologia , Cumarínicos/farmacologia , Polifenóis/farmacologia , Wikstroemia/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Biflavonoides/química , Biflavonoides/isolamento & purificação , Linhagem Celular Tumoral , Cumarínicos/química , Cumarínicos/isolamento & purificação , Humanos , Estrutura Molecular , Polifenóis/química , Polifenóis/isolamento & purificação , Espectroscopia de Prótons por Ressonância Magnética , Rizoma/química , Estereoisomerismo
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