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1.
Virus Genes ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38722491

RESUMEN

H6 avian influenza virus is widely prevalent in wild birds and poultry and has caused human infection in 2013 in Taiwan, China. During our active influenza surveillance program in wild waterfowl at Poyang Lake, Jiangxi Province, an H6N2 AIV was isolated and named A/bean goose/JiangXi/452-4/2013(H6N2). The isolate was characterized as a typical low pathogenic avian influenza virus (LPAIV) due to the presence of the amino acid sequence PQIETR↓GLFGAI at the cleavage site of the hemagglutinin (HA) protein. The genetic evolution analysis revealed that the NA gene of the isolate originated from North America and exhibited the highest nucleotide identity (99.29%) with a virus recovered from wild bird samples in North America, specifically A/bufflehead/California/4935/2012(H11N2). Additionally, while the HA and PB1 genes belonged to the Eurasian lineage, they displayed frequent genetic interactions with the North American lineage. The remaining genes showed close genetic relationships with Eurasian viruses. The H6N2 isolate possessed a complex genome, indicating it is a multi-gene recombinant virus with genetic material from both Eurasian and North American lineages.

2.
J Ethnopharmacol ; 323: 117698, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38171464

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Polycystic ovary syndrome (PCOS) is a prevalent female endocrine condition that significantly affects women of all age groups and is characterized by metabolic dysfunction. The efficacy of existing pharmaceutical interventions for the treatment of PCOS remains inadequate. With a rich history and cultural significance spanning thousands of years, Traditional Chinese Medicine (TCM) is extensively employed for treating a variety of ailments and can serve as a supplementary therapy for managing PCOS. Multiple clinical observations and laboratory tests have unequivocally demonstrated the substantial effectiveness and safety of TCM formulae in treating PCOS, and further investigations are currently in progress. AIM OF THE STUDY: To summarize the TCM formulae commonly employed in the clinical management of PCOS, examine their therapeutic benefits, investigate their mechanism of action, active constituents, and establish the correlation between efficacy, mechanism of action, and active constituents. MATERIALS AND METHODS: We conducted a comprehensive search on PubMed, Web of Science, and China national knowledge infrastructure (CNKI) using the following keywords: "Polycystic Ovary Syndrome", "Traditional Chinese Medicine Decoctions", "Traditional Chinese Medicine formulae", "Traditional Chinese Medicine", "Clinical Observation", "Mechanism", "Treatment", "Pharmacology", and various combinations of these terms. From January 1, 2006 until October 7, 2023, (inclusive). RESULTS: This paper summarized the clinical effectiveness, mechanism of action, and active components of 8 TCM formulae for the treatment of PCOS. Our research indicates that TCM formulae can potentially treat PCOS by enhancing the levels of hyperandrogenism and other endocrine hormones, decreasing insulin resistance and hyperinsulinemia, and controlling chronic low-grade inflammation, among other modes of action. In addition, we found an association between epigenetics and TCM formulae for the treatment of PCOS. CONCLUSION: TCM formulae have specific advantages in the treatment of Polycystic Ovary Syndrome (PCOS). They achieve therapeutic benefits by targeting several pathways and connections, attracting considerable interest and playing a vital role in the treatment of PCOS. TCM formulae can be used as an adjunctive therapy for the treatment of PCOS.


Asunto(s)
Resistencia a la Insulina , Síndrome del Ovario Poliquístico , Femenino , Humanos , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Síndrome del Ovario Poliquístico/metabolismo , Medicina Tradicional China , Inflamación , China
3.
ACS Omega ; 8(45): 43285-43294, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38024707

RESUMEN

Rare ginsenosides with major pharmacological effects are barely present in natural ginseng and are required to be obtained by transformation. In the current study, ginsenoside Rb1 was chemically transformed with the involvement of ethanol molecules to prepare rare ginsenosides using the synthesized heterogeneous catalyst 12-HPW@MeSi. A total of 16 transformation products were obtained and identified using high-performance liquid chromatography coupled with multistage tandem mass spectrometry and high-resolution mass spectrometry. Ethanol molecules were involved in the production of 6 transformation products by adding to the C-20(21), C-20(22), or C-24(25) double bonds on the aglycone to produce ethoxyl groups at the C-25 and C-20 positions. Transformation pathways of ginsenoside Rb1 are summarized, which involve deglycosylation, elimination, cycloaddition, epimerization, and addition reactions. In addition, 12-HPW@MeSi was recyclable through a simple centrifugation, maintaining an 85.1% conversion rate of Rb1 after 3 cycles. This work opens up an efficient and recycled process for the preparation of rare ginsenosides with the involvement of organic molecules.

4.
Future Microbiol ; 18: 735-749, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37526178

RESUMEN

Aim: Our primary objective was to investigate the protective effects and mechanisms of isovanillic acid in mice infected with Staphylococcus aureus Newman. Methods: In vitro coagulation assays were used to validate vWbp and Coa as inhibitory targets of isovanillic acid. The binding mechanism of isovanillic acid to vWbp and Coa was investigated using molecular docking and point mutagenesis. Importantly, a lethal pneumonia mouse model was used to assess the effect of isovanillic acid on survival and pathological injury in mice. Results & Conclusion: Isovanillic acid reduced the virulence of S. aureus by directly binding to inhibit the clotting activity of vWbp and Coa, thereby reducing lung histopathological damage and improving the survival rate in mice with pneumonia.


Asunto(s)
Coagulasa , Infecciones Estafilocócicas , Ratones , Animales , Coagulasa/metabolismo , Staphylococcus aureus/metabolismo , Simulación del Acoplamiento Molecular , Infecciones Estafilocócicas/prevención & control
5.
Molecules ; 28(15)2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37570602

RESUMEN

Bupleurum chinense DC. and Bupleurum scorzonerifolium Willd. have different clinical efficacies, with the former typically used to treat typhoid fever and the latter mainly used to clear liver heat. The differences in their clinical efficacy are closely related to their complex chemical composition, especially the active components. In this study, the saponins and volatile oils in two varieties of Radix Bupleuri grown in different regions were extracted and analyzed using high-performance liquid chromatography (HPLC) and gas chromatography coupled with mass spectrometry (MS), and the absolute contents of five saikosaponins were accurately quantified using an established HPLC-MS method in the multiple reaction monitoring mode. Multivariate statistical analysis was performed to reveal the difference in the active components between the two varieties. The saikosaponin content was significantly affected by variety and growing region, with all five saikosaponins being significantly higher in Bupleurum chinense DC. than in Bupleurum scorzonerifolium Willd. The results of principal component analysis and hierarchical cluster analysis show a clear distinction between the two varieties in terms of both saponins and volatile oils. Twenty-one saponins, including saikosaponin b2 and b1, and fifty-two volatile oils, including 2-tetradecyloxirane and chloromethyl cyanide, were screened and identified as differential compounds contributing to the significant difference between the two varieties. These compounds may also be responsible for the difference in clinical efficacy between Bupleurum chinense DC. and Bupleurum scorzonerifolium Willd. All the results suggest that the accumulation and diversity of active components in Radix Bupleuri are significantly affected by the variety. In contrast to previous reports, this study provides the absolute contents of five saikosaponins in Radix Bupleuri of different varieties and reduces the influence of the growing region on the analytical results by collecting samples from different regions. The results of this study may provide a reference for the identification and quality evaluation of different varieties of Radix Bupleuri.


Asunto(s)
Bupleurum , Aceites Volátiles , Ácido Oleanólico , Saponinas , Bupleurum/química , Cromatografía Líquida de Alta Presión/métodos , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas , Saponinas/análisis , Ácido Oleanólico/análisis , Aceites Volátiles/análisis , Raíces de Plantas/química
6.
Cancer Nurs ; 46(5): 394-404, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37607375

RESUMEN

BACKGROUND: Cancer-related fatigue is one of the most common symptoms reported by cancer patients and is considered to be related to inflammation. OBJECTIVE: This study aimed to explore the effects of nutritional support based on the dietary anti-inflammatory index on cancer-related fatigue in lung cancer patients undergoing chemotherapy. METHODS: This was a randomized controlled trial with 106 lung cancer patients who were divided into either the anti-inflammatory diet group (n = 53) or the usual diet group (n = 53) for 3 months. The primary outcome was cancer-related fatigue. Secondary outcomes included high sensitivity C-reactive protein (hs-CRP) concentrations, nutritional status, and quality of life. Repeated-measures analysis of variance was used to examine the effectiveness of this intervention. RESULTS: The anti-inflammatory diet improved fatigue (-1.99 ± 1.78, P < .001), hs-CRP levels (-4.15 [-11.87, -0.58], P < .001), Patient-Generated Subjective Global Assessment (-2.53 ± 3.11, P = .030), and albumin concentrations (2.83 ± 0.59, P < .001) compared with the usual diet after 3 months. Simultaneously, in the repeated-measures analysis of variance, the differences in fatigue ( F = 5.536, P < .001), hs-CRP levels ( F = 6.918, P < .001), and albumin concentrations ( F = 2.727, P = .048) were statistically significant for the group-by-time interaction. CONCLUSION: The study provided evidence for the positive effect of nutritional support based on the dietary anti-inflammatory index on cancer-related fatigue, hs-CRP levels, nutritional status, and quality of life in lung cancer patients undergoing chemotherapy. IMPLICATION FOR PRACTICE: With an anti-inflammatory diet, nurses can help these patients improve their overall quality of life.


Asunto(s)
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/tratamiento farmacológico , Proteína C-Reactiva/análisis , Calidad de Vida , Dieta/efectos adversos , Apoyo Nutricional , Antiinflamatorios , Fatiga/etiología
7.
Minerva Endocrinol (Torino) ; 48(2): 160-171, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-33103870

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex endocrine disorder with well-established metabolic abnormalities. In the present study, untargeted metabolomics technology was applied to analyze the serum and follicular fluid samples from women with polycystic ovary syndrome and healthy controls using 1H nuclear magnetic resonance (NMR). METHODS: Seventy samples for PCOS analysis were collected in hospital of Shandong University of Traditional Chinese Medicine (Jinan, China), NMR was used as analytical technology and multivariate analysis was applied to analyze metabolomics difference in PCOS and healthy controls. RESULTS: Significant metabolic differences were found in both serum and follicular fluid samples with orthogonal partial least-squares discriminant analysis (OPLS-DA). Three discriminated metabolites (1-Methylhistidine, threonine and Citrate) in both serum and follicular fluid were altered in PCOS patients. Abnormal energy metabolism, lipid metabolism and amino acid metabolism were detected in PCOS patients. Furthermore, more significantly changed amino acids were discovered in follicular fluid samples. CONCLUSIONS: Our findings would provide a resource for further investigations on metabolic disturbance in PCOS patients.


Asunto(s)
Síndrome del Ovario Poliquístico , Humanos , Femenino , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/patología , Líquido Folicular/metabolismo , Metabolómica , Espectroscopía de Resonancia Magnética , Aminoácidos/metabolismo
8.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-1010292

RESUMEN

OBJECTIVE@#To explore the underlying mechanism of inhibition by Jinkui Shenqi Pills (JKSQP) on glucocorticoid-enhanced axial length elongation in experimental lens-induced myopia (LIM) guinea pigs.@*METHODS@#Sixty 2-week old male guinea pigs were randomly divided into 4 groups with 15 guinea pigs in each group, according to the random numbers generated by SPSS software: control, LIM, saline and JKSQP groups. The control group includes animals with no treatment, while the guinea pigs in the other 3 groups received lens-induced myopization on the right eyes throughout the experiment (for 8 weeks). The saline and JKSQP groups were given daily intraperitoneal injections of 10 mg/kg hydrocortisone for 2 consecutive weeks at the same time, and then orally administered either saline or JKSQP [13.5 g/(kg•d) for 6 consecutive weeks. Body weight, anal temperature and animal appearance were observed and recorded to evaluate the GC-associated symptoms. The ocular parameters, including refraction and axial length, were measured by streak retinoscopy and A-scan ultrasonography, respectively. The levels of plasma hormones associated with the hypothalamic-pituitary-adrenal axis (HPAA), including free triiodothyronine, free thyroxine, estradiol and testosterone, were measured by radioimmunoassay, and cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate were measured by enzyme-linked immunosorbent assay. In addition, the mRNA and protein expressions of retinal amphiregulin (AREG) was measured by quantitative real-time polymerase chain reaction and Western blotting, respectively.@*RESULTS@#JKSQP effectively increased body weight and anal temperature, improved animal appearance and suppressed axial length elongation in glucocorticoid-enhanced myopic guinea pigs with normalization of 4 HPAA-associated plasma hormones (all P<0.05). The plasma level of cAMP was significantly increased, whereas the plasma level of cGMP and the mRNA and protein expressions of retinal AREG were decreased after treatment with JKSQP (all P<0.05).@*CONCLUSION@#JKSQP exhibited a significant inhibitory effect on axial length elongation with decreased expression of AREG in the retina, and normalized 4 HPAA-associated plasma hormones and the expression of cAMP and cGMP in GC-enhanced myopic guinea pigs.


Asunto(s)
Masculino , Animales , Cobayas , Glucocorticoides , Sistema Hipotálamo-Hipofisario , Sistema Hipófiso-Suprarrenal , Miopía/metabolismo , Peso Corporal , ARN Mensajero , Modelos Animales de Enfermedad
10.
3 Biotech ; 12(11): 289, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36276459

RESUMEN

A novel ß-glucosidase (Thglu3) was identified from Thermotoga sp. which had biotransformation activity for notoginsenoside R1 (NR-R1). Sequence analysis of Thglu3 revealed that it could be classified into glycoside hydrolase family 3 (GH3). The gene encoding a 719-amino acid protein was cloned and expressed in Escherichia coli. The recombinant enzyme was purified, and its molecular weight was approximately 81 kDa. The recombinant Thglu3 exhibited an optimal activity at 75 °C and pH 6.4. The ß-glucosidase had high selectivity for cleaving the outer glucose moiety at the C20 position of NR-R1, which produced the more pharmacologically active notoginsenoside R2 (NR-R2). Under the optimal reaction conditions for gram-scale production, 30 g NR-R1 was transformed to NR-R2 using 20 g crude enzyme at pH 6.4 and 75 °C within 1 h with a molar yield of 93%. This study was the first report of the highly efficient and selective gram-scale transformation of NR-R2 from NR-R1 by a thermophilic ß-glucosidase.

11.
Molecules ; 27(15)2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35956782

RESUMEN

The quality of Radix Bupleuri is greatly affected by its growing environment. In this study, Radix Bupleuri samples that were harvested from seven different regions across northwest China were examined by high-performance liquid chromatography (HPLC) and gas chromatography (GC) coupled with mass spectrometry (MS) to reveal significant differences in quality contributed by the cultivation region. An HPLC-MS method was firstly established and used in the multiple reaction monitoring mode for the quantitative analysis of five saikosaponins in Radix Bupleuri so as to evaluate the difference in the absolute content of saikosaponins attributable to the cultivation region. The effect on the components of Radix Bupleuri was further investigated based on the profiles of the representative saponins and volatile compounds, which were extracted from the Radix Bupleuri samples and analyzed by HPLC-MS and GC-MS. Multivariate statistical analysis was employed to differentiate the Radix Bupleuri samples cultivated in different regions and to discover the differential compositions. The developed quantitative method was validated to be accurate, stable, sensitive, and repeatable for the determination of five saikosaponins. Further statistical tests revealed that the collected Radix Bupleuri samples were distinctly different from each other in terms of both saponins and volatile compounds, based on the provinces where they were grown. In addition, twenty-eight saponins and fifty-eight volatile compounds were identified as the differentially accumulated compositions that contributed to the discrimination of the Radix Bupleuri samples. The Radix Bupleuri samples grown in Shouyang county showed the highest content of saikosaponins. All of the results indicated that the cultivation region significantly affected the accumulation and diversity of the main chemical components of Radix Bupleuri. The findings of this research provide insights into the effect of the cultivation region on the quality of Radix Bupleuri and the differentiation of Radix Bupleuri cultivated in different regions based on the use of HPLC-MS and GC-MS combined with multivariate statistical analysis.


Asunto(s)
Bupleurum , Medicamentos Herbarios Chinos , Saponinas , Bupleurum/química , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas , Saponinas/análisis
12.
Molecules ; 27(13)2022 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-35807341

RESUMEN

Biotransformation of specific saponins in the valuable medical plants to increase their bioavailability and pharmaceutical activities has attracted more and more attention. A gene encoding a thermophilic glycoside hydrolase from Fervidobaterium pennivorans DSM9078 was cloned and expressed in Escherichia coli. The purified recombinant enzyme, exhibiting endoglucanase cellulase activity, was used to transform gypenoside XLIX into gylongiposide I via highly selective and efficient hydrolysis of the glucose moiety linked to the C21 position in gypenoside XLIX. Under the optimal reaction conditions for large scale production of gylongiposide I, 35 g gypenoside XLIX was transformed by using 20 g crude enzyme at pH 6.0 and 80 °C for 4 h with a molar yield of 100%. Finally, 11.51 g of gylongiposide I was purified using a silica gel column with 91.84% chromatographic purity. Furthermore, inhibitory activities of gypenoside XLIX and gylongiposide I against Enterovirus 71 (EV71) were investigated. Importantly, the EC50 of gypenoside XLIX and gylongiposide I calculated from viral titers in supernatants was 3.53 µM and 1.53 µM, respectively. Moreover, the transformed product gylongiposide I has better anti-EV71 activity than the glycosylated precursor. In conclusion, this enzymatic method would be useful in the large-scale production of gylongiposide I, which would be a novel potent anti-EV71 candidate.


Asunto(s)
Enterovirus Humano A , Enterovirus , Saponinas , Antivirales/metabolismo , Antivirales/farmacología , Biotransformación , Enterovirus/metabolismo , Gynostemma/química , Imidazoles , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Saponinas/química , Sulfonamidas , Tiofenos , Triterpenos
13.
ISA Trans ; 122: 271-280, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33992419

RESUMEN

This paper presents a collaborative obstacle avoidance algorithm of multiple bionic snake robots in fluid based on IB-LBM. The method can make the multiple bionic snake robots avoid different obstacles in the fluid under the control of the improved Serpenoid curve function. The proposed method has high parallelism, can simulate the complex non-linear phenomenon of the multiple snake robots, deal with the complex boundary conditions of the robot, and reduce the conversion of the computational grid. Firstly, a non-linear fluid model is established by LBM, which solves the non-linear problem that the classical Navier-Stokes equations cannot explain the random motion. Secondly, the force source boundary model of multiple bionic snake robots is established by IBM, which saves the calculation time, improves the calculation efficiency and system stability. After that, each bionic snake robot is given a special force to make the robots collaborate with each other and non-colliding with each other in the process of the obstacle avoidance. Finally, through simulation experiments, the trajectory of multiple bionic snake robots avoiding different number of the obstacles in the fluid is analyzed and the collaborative obstacle avoidance process of multiple bionic snake robots in fluid is observed. The validity of the collaborative obstacle avoidance algorithm of multiple bionic snake robots in fluid based on the IB-LBM is verified.


Asunto(s)
Biónica , Robótica , Algoritmos , Simulación por Computador , Movimiento (Física) , Robótica/métodos
14.
Am J Chin Med ; 49(5): 1063-1092, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34107858

RESUMEN

Coronavirus disease (COVID-19) is a new infectious disease associated with high mortality, and traditional Chinese medicine decoctions (TCMDs) have been widely used for the treatment of patients with COVID-19 in China; however, the impact of these decoctions on severe and critical COVID-19-related mortality has not been evaluated. Therefore, we aimed to address this gap. In this retrospective cohort study, we included inpatients diagnosed with severe/critical COVID-19 at the Tongren Hospital of Wuhan University and grouped them depending on the recipience of TCMDs (TCMD and non-TCMD groups). We conducted a propensity score-matched analysis to adjust the imbalanced variables and treatments and used logistic regression methods to explore the risk factors associated with in-hospital death. Among 282 patients with COVID-19 who were discharged or died, 186 patients (66.0%) received TCMD treatment (TCMD cohort) and 96 (34.0%) did not (non-TCMD cohort). After propensity score matching at a 1:1 ratio, 94 TCMD users were matched to 94 non-users, and there were no significant differences in baseline clinical variables between the two groups of patients. The all-cause mortality was significantly lower in the TCMD group than in the non-TCMD group, and this trend remained valid even after matching (21.3% [20/94] vs. 39.4% [37/94]). Multivariable logistic regression model showed that disease severity (odds ratio: 0.010; 95% CI: 0.003, 0.037; [Formula: see text]¡ 0.001) was associated with increased odds of death and that TCMD treatment significantly decreased the odds of in-hospital death (odds ratio: 0.115; 95% CI: 0.035, 0.383; [Formula: see text]¡ 0.001), which was related to the duration of TCMD treatment. Our findings show that TCMD treatment may reduce the mortality in patients with severe/critical COVID-19.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19/mortalidad , Medicamentos Herbarios Chinos/administración & dosificación , Anciano , COVID-19/patología , Enfermedad Crítica , Femenino , Humanos , Masculino , Medicina Tradicional China , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
15.
Sci Rep ; 11(1): 9375, 2021 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-33931675

RESUMEN

Comprehensive comparison of paleoclimate change based on records constrained by precise chronology and high-resolution is essential to explore the correlation and interaction within earth climate systems. Here, we propose a new stalagmite-based multidecadal resolved Asian summer monsoon (ASM) record spanning the past thirty-seven thousand years (ka BP, before AD 1950) from Furong Cave, southwestern China. This record is consistent with the published Chinese stalagmite sequences and shows that the dominant controls of the ASM dynamics include not only insolation and solar activity but also suborbital-scale hydroclimate events in the high latitudes of the northern hemisphere, such as the Heinrich events, Bølling-Allerød (BA), and Younger Dryas (YD). Benefit from the unprecedented accurate chronology, the timings of these events are precisely dated, with uncertainties of, at most, 40 years (2σ). The onset of the weak ASM during the YD began at 12.92 ka BP and lasted for 430 years. The occurrence of the 200-yr Older Dryas during the BA period was dated from 13.87 to 14.06 ka BP. The durations of the three Heinrich (H) events, H1, H2, and H3, are 14.33-18.29, 23.77-24.48, and 28.98-30.46 ka BP, respectively. Furong record shows surprisingly variable onset transitions of 980, 210, and 40 years for the corresponding weak ASM events. These discrepancies suggest different influences of the H events on ASM dynamics. During the periods of H 1-3, the obvious difference between our Furong record and NGRIP δ18O record indicated the decoupling correlation between the mid-low latitudes and high latitudes. On the other hand, synchronous climate change in high and low latitudes suggests another possibility which different to the dominant role of Northern high latitudes in triggering global climate change. Our high quality records also indicate a plausible different correlation between the high and mid-low latitudes under glacial and inter-glacial background, especially for the ASM regimes.

16.
N Biotechnol ; 62: 49-56, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-33486119

RESUMEN

The coordinated action of carbohydrate-active enzymes has mainly been evaluated for the purpose of complete saccharification of plant biomass (lignocellulose) to sugars. By contrast, the coordinated action of accessory hemicellulases on xylan debranching and recovery is less well characterized. Here, the activity of two family GH115 α-glucuronidases (SdeAgu115A from Saccharophagus degradans, and AxyAgu115A from Amphibacillus xylanus) on spruce arabinoglucuronoxylan (AGX) was evaluated in combination with an α-arabinofuranosidase from families GH51 (AniAbf51A, aka E-AFASE from Aspergillus niger) and GH62 (SthAbf62A from Streptomyces thermoviolaceus). The α-arabinofuranosidases boosted (methyl)-glucuronic acid release by SdeAgu115A by approximately 50 % and 30 %, respectively. The impact of the α-arabinofuranosidases on AxyAgu115A activity was comparatively low, motivating its structural characterization. The crystal structure of AxyAgu115A revealed increased length and flexibility of the active site loop compared to SdeAgu115A. This structural difference could explain the ability of AxyAgu115A to accommodate more highly substituted arabinoglucuronoxylan, and inform enzyme selections for improved AGX recovery and use.


Asunto(s)
Bacillaceae/enzimología , Glicósido Hidrolasas/química , Glicósido Hidrolasas/metabolismo , Modelos Moleculares
17.
J Colloid Interface Sci ; 587: 550-560, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33220954

RESUMEN

Biomimetic construction of artificial photosystem capable of converting light energy to chemical energy is a promising strategy in solving the increasing serious energy and environmental problems. Herein, we present a new strategy to construct light-harvesting antenna via hierarchical co-assembly of short-peptide and porphyrin and subsequent self-metallization process. The hierarchically organized antenna exhibits both excellent photocatalytic performance and remarkable sustainability under strong light irradiation (35000 lx) and extraordinary sensitivity to weak light (700 lx). In such cases, light energy can be converted into chemical energy and stored in the energy-storage molecules (nicotinamide adenine dinucleotide, NADH) even under weak light irradiation. This provides a promising step towards an artificial photosystem that can utilize weak light. Moreover, the structures and properties of the antenna are dependent on the competition of short-peptide self-assembling and co-assembling with porphyrin molecules and can be regulated by their molar ratio. This provides new insights into the design and construction of light-harvesting antennas with integrated functionality via precise control of pigments aggregation and coupling of different functional units.

18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-879819

RESUMEN

OBJECTIVE@#To study the clinical effect of continuous subcutaneous insulin infusion (CSⅡ) versus multiple daily injection (MDI) on blood glucose control in children with type 1 diabetes mellitus (T1DM).@*METHODS@#A retrospective analysis was performed on the medical data of 91 children with T1DM who were treated with CSⅡ for more than 1 year and 75 children with T1DM who were treated with MDI. The two groups were compared in terms of glycosylated hemoglobin (HbA1C) and the recurrence of diabetic ketoacidosis (DKA) to evaluate the difference in the efficacy during the 3-year follow-up. A survey was conducted for the children in the CSⅡ group and their family members to investigate the degree of satisfaction with insulin pump.@*RESULTS@#There was no significant difference in age, sex, and course of diabetes between the CSⅡ and MDI groups at disease onset and in the first year, the second year, and the third year of follow-up (@*CONCLUSIONS@#Children with T1DM treated with CSⅡ have a better control of blood glucose than those treated with MDI, and children and their family members are satisfied with CSⅡ treatment. Therefore, it holds promise for clinical application.


Asunto(s)
Niño , Humanos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Cetoacidosis Diabética , Estudios de Seguimiento , Insulinas , Estudios Retrospectivos
19.
Bioorg Chem ; 105: 104367, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33080495

RESUMEN

Human Carboxylesterase 2A (hCES2A), one of the most important serine hydrolases, plays crucial roles in the hydrolysis and the metabolic activation of a wide range of esters and amides. Increasing evidence has indicated that potent inhibition on intestinal hCES2A may reduce the excessive accumulation of SN-38 (the hydrolytic metabolite of irinotecan with potent cytotoxicity) in the intestinal tract and thereby alleviate the intestinal toxicity triggered by irinotecan. In this study, more than sixty natural alkaloids have been collected and their inhibitory effects against hCES2A are assayed using a fluorescence-based biochemical assay. Following preliminary screening, seventeen alkaloids are found with strong to moderate hCES2A inhibition activity. Primary structure-activity relationships (SAR) analysis of natural isoquinoline alkaloids reveal that the benzo-1,3-dioxole group and the aromatic pyridine structure are beneficial for hCES2A inhibition. Further investigations demonstrate that a steroidal alkaloid reserpine exhibits strong hCES2A inhibition activity (IC50 = 0.94 µM) and high selectivity over other human serine hydrolases including hCES1A, dipeptidyl peptidase IV (DPP-IV), butyrylcholinesterase (BChE) and thrombin. Inhibition kinetic analyses demonstrated that reserpine acts as a non-competitive inhibitor against hCES2A-mediated FD hydrolysis. Molecular docking simulations demonstrated that the potent inhibition of hCES2A by reserpine could partially be attributed to its strong σ-π and S-π interactions between reserpine and hCES2A. Collectively, our findings suggest that reserpine is a potent and highly selective inhibitor of hCES2A, which can be served as a promising lead compound for the development of more efficacious and selective alkaloids-type hCES2A inhibitors for biomedical applications.


Asunto(s)
Alcaloides/farmacología , Productos Biológicos/farmacología , Carboxilesterasa/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Alcaloides/síntesis química , Alcaloides/química , Productos Biológicos/síntesis química , Productos Biológicos/química , Carboxilesterasa/metabolismo , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Cinética , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad
20.
Chin Med J (Engl) ; 133(22): 2731-2742, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-32889913

RESUMEN

BACKGROUND: Despite the recent large number of studies comparing endoscopic and laparoscopic resection for small gastrointestinal stromal tumors (GISTs) (diameter ≤ 5 cm), the results remain conflicting. The objective of this work was to perform a cumulative meta-analysis to assess the advantages and disadvantages of endoscopic resection vs. laparoscopic resection. METHODS: The meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We searched medical databases up to January 2020. Meta-analytical random or fixed effects models were used in pooled analyses. Meta-regression, cumulative meta-analyses, and subgroup analyses were performed to improve the accuracy of the conclusion. Sensitivity analyses were applied to assess the robustness of the results. RESULTS: A total of 12 cohort studies with 1383 participants comparing endoscopic resection and laparoscopic resection were identified, while three cohort studies with 167 participants comparing endoscopic resection and laparoscopic and endoscopic cooperative surgery were found. We found that endoscopic resection had shorter operation times (weighted mean difference [WMD] = -27.1 min, 95% confidence interval [CI]: -40.8 min to -13.4 min) and lengths of hospital stay (WMD = -1.43 d, 95% CI: -2.31 d to -0.56 d) than did laparoscopic resection. The results were stable and reliable. There were no significant differences in terms of blood loss, hospitalization costs, incidence of complications or recurrence rates. For tumor sizes 2 - 5 cm, endoscopic resection increased the risk of positive margins (relative risk [RR] = 5.78, 95% CI: 1.31 - 25.46). Although operation times for endoscopic resection were shorter than those of laparoscopic and endoscopic cooperative surgery (WMD = -41.03 min, 95% CI: -59.53 min to -22.54 min), there was a higher incidence of complications (RR = 4.03, 95% CI: 1.57 - 10.34). CONCLUSIONS: In general, endoscopic resection is an alternative method for gastric GISTs ≤ 5 cm. Laparoscopic and endoscopic cooperative surgery may work well in combination. Further randomized controlled trials are recommended to validate or update these results.


Asunto(s)
Tumores del Estroma Gastrointestinal , Laparoscopía , Neoplasias Gástricas , Gastrectomía , Tumores del Estroma Gastrointestinal/cirugía , Humanos , Tiempo de Internación , Recurrencia Local de Neoplasia/cirugía , Complicaciones Posoperatorias , Neoplasias Gástricas/cirugía , Resultado del Tratamiento
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