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1.
Skin Res Technol ; 30(1): e13571, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38196164

RESUMEN

BACKGROUND: Nuclear pleomorphism and tumor microenvironment (TME) play a critical role in cancer development and progression. Identifying most predictive nuclei and TME features of basal cell carcinoma (BCC) may provide insights into which characteristics pathologists can use to distinguish and stratify this entity. OBJECTIVES: To develop an automated workflow based on nuclei and TME features from basaloid cell tumor regions to differentiate BCC from trichoepithelioma (TE) and stratify BCC into high-risk (HR) and low-risk (LR) subtypes, and to identify the nuclear and TME characteristics profile of different basaloid cell tumors. METHODS: The deep learning systems were trained on 161 H&E -stained sections which contained 51 sections of HR-BCC, 50 sections of LR-BCC and 60 sections of TE from one institution (D1), and externally and independently validated on D2 (46 sections) and D3 (76 sections), from 2015 to 2022. 60%, 20% and 20% of D1 data were randomly splitted for training, validation and testing, respectively. The framework comprised four stages: tumor regions identification by multi-head self-attention (MSA) U-Net, nuclei segmentation by HoVer-Net, quantitative feature by handcrafted extraction, and differentiation and risk stratification classifier construction. Pixel accuracy, precision, recall, dice score, intersection over union (IoU) and area under the curve (AUC) were used to evaluate the performance of tumor segmentation model and classifiers. RESULTS: MSA-U-Net model detected tumor regions with 0.910 precision, 0.869 recall, 0.889 dice score and 0.800 IoU. The differentiation classifier achieved 0.977 ± 0.0159, 0.955 ± 0.0181, 0.885 ± 0.0237 AUC in D1, D2 and D3, respectively. The most discriminative features between BCC and TE contained Homogeneity, Elongation, T-T_meanEdgeLength, T-T_Nsubgraph, S-T_HarmonicCentrality, S-S_Degrees. The risk stratification model can well predict HR-BCC and LR-BCC with 0.920 ± 0.0579, 0.839 ± 0.0176, 0.825 ± 0.0153 AUC in D1, D2 and D3, respectively. The most discriminative features between HR-BCC and LR-BCC comprised IntensityMin, Solidity, T-T_minEdgeLength, T-T_Coreness, T-T_Degrees, T-T_Betweenness, S-T_Degrees. CONCLUSIONS: This framework hold potential for future use as a second opinion helping inform diagnosis of BCC, and identify nuclei and TME features related with malignancy and tumor risk stratification.


Asunto(s)
Carcinoma Basocelular , Aprendizaje Profundo , Neoplasias Cutáneas , Humanos , Microambiente Tumoral , Carcinoma Basocelular/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Medición de Riesgo
2.
Chemphyschem ; 24(9): e202200947, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-36715013

RESUMEN

Planar, tubular, cage-like, and bilayer boron clusters Bn +/0/- (n=3∼48) have been observed in joint experimental and theoretical investigations in the past two decades. Based on extensive global searches augmented with first-principles theory calculations, we predict herein the smallest perfect core-shell octahedral borospherene Oh B@B38 + (1) and its endohedral metallo-borospherene analogs Oh Be@B38 (2), and Oh Zn@B38 (3) which, with an octa-coordinate B, Be or Zn atom located exactly at the center, turn out to be the well-defined global minima of the systems highly stable both thermodynamically and dynamically. B@B38 + (1) represents the first boron-containing molecule reported to date which contains an octa-coordinate B center covalently coordinated by eight face-capping boron atoms at the corners of a perfect cube in the first coordination sphere. Detailed natural bonding orbital (NBO) and adaptive natural density partitioning (AdNDP) bonding analyses indicate that these high-symmetry core-shell complexes X@B38 +/0/- (X=B, Be, Zn) as super-noble gas atoms follow the octet rule in coordination bonding patterns (1S2 1P6 ), with one delocalized 9c-2e S-type coordination bond and three delocalized 39c-2e P-type coordination bonds formed between the octa-coordinate X center and its octahedral Oh B38 ligand to effectively stabilize the systems. Their IR, Raman, and UV-Vis spectra are computationally simulated to facilitate their spectroscopic characterizations.

3.
Chemphyschem ; 24(9): e202300222, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37129295

RESUMEN

The front cover artwork is provided by Prof. Si-Dian Li's group at Shanxi University, China. The image shows the smallest perfect core-shell octahedral borospherene Oh B@B38 + and its endohedral metallo-borospherene analogs Oh Be@B38 and Oh Zn@B38 obtained at first-principles theory. Read the full text of the Research Article at 10.1002/cphc.202200947.

4.
Appl Microbiol Biotechnol ; 107(11): 3579-3591, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37115252

RESUMEN

2'-Fucosyllactose (2'-FL) is known for its ability to provide various health benefits to infants, such as gut maturation, pathogen resistance, improved immunity, and nervous system development. However, the production of 2'-FL using α-L-fucosidases is hindered by the lack of low-cost natural fucosyl donors and high-efficiency α-L-fucosidases. In this work, a recombinant xyloglucanase from Rhizomucor miehei (RmXEG12A) was applied to produce xyloglucan-oligosaccharide (XyG-oligos) from apple pomace. Then, an α-L-fucosidase gene (PbFucB) was screened from the genomic DNA of Pedobacter sp. CAU209 and expressed in Escherichia coli. The capability of purified PbFucB to catalyze XyG-oligos and lactose to synthesize 2'-FL was further evaluated. The deduced amino acid sequence of PbFucB shared the highest identity (38.4%) with that of other reported α-L-fucosidases. PbFucB showed the highest activity at pH 5.5 and 35 °C. It catalyzed the hydrolysis of 4-nitrophenyl-α-L-fucopyranoside (pNP-Fuc, 20.3 U mg-1), 2'-FL (8.06 U mg-1), and XyG-oligos (0.43 U mg-1). Furthermore, PbFucB demonstrated a high enzymatic conversion rate in 2'-FL synthesis with pNP-Fuc or apple pomace-derived XyG-oligos as donors and lactose as acceptor. Under the optimized conditions, PbFucB converted 50% of pNP-Fuc or 31% of the L-fucosyl residue in XyG-oligos into 2'-FL. This work elucidated an α-L-fucosidase that mediates the fucosylation of lactose and provided an efficient enzymatic strategy to synthesize 2'-FL either from artificial pNP-Fuc or natural apple pomace-derived XyG-oligos. KEY POINTS: • Xyloglucan-oligosaccharide (XyG-oligos) was produced from apple pomace by a xyloglucanase from Rhizomucor miehei. • An α-L-fucosidase (PbFucB) from Pedobacter sp. CAU209 shared the highest identity (38.4%) with reported α-L-fucosidases. •PbFucB synthesized 2'-FL using apple pomace-derived XyG-oligos and lactose with a conversion ratio of 31%.


Asunto(s)
Malus , Pedobacter , Lactante , Humanos , alfa-L-Fucosidasa/genética , alfa-L-Fucosidasa/metabolismo , Malus/metabolismo , Lactosa/metabolismo , Oligosacáridos/metabolismo
5.
Molecules ; 28(9)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37175301

RESUMEN

Transition-metal-doped boron nanoclusters exhibit unique structures and bonding in chemistry. Using the experimentally observed seashell-like borospherenes C2 B28-/0 and Cs B29- as ligands and based on extensive first-principles theory calculations, we predict herein a series of novel transition-metal-centered endohedral seashell-like metallo-borospherenes C2 Sc@B28- (1), C2 Ti@B28 (2), C2 V@B28+ (3), and Cs V@B292- (4) which, as the global minima of the complex systems, turn out to be the boron analogues of dibenzenechromium D6h Cr(C6H6)2 with two B12 ligands on the top and bottom interconnected by four or five corner boron atoms on the waist and one transition-metal "pearl" sandwiched at the center in between. Detailed molecular orbital, adaptive natural density partitioning (AdNDP), and iso-chemical shielding surface (ICSS) analyses indicate that, similar to Cr(C6H6)2, these endohedral seashell-like complexes follow the 18-electron rule in bonding patterns (1S21P61D10), rendering spherical aromaticity and extra stability to the systems.

6.
Zhongguo Zhong Yao Za Zhi ; 48(8): 2116-2125, 2023 Apr.
Artículo en Zh | MEDLINE | ID: mdl-37282900

RESUMEN

This study aims to separate and characterize self-assembled nanoparticles(SAN) from Shaoyao Gancao Decoction(SGD) and determine the content of active compounds. Further, we aimed to observe the therapeutic effect of SGD-SAN on imiquimod-induced psoriasis in mice. The separation of SGD was performed by dialysis, and the separation process was optimized by single factor experiment. The SGD-SAN isolated under the optimal process was characterized, and the content of gallic acid, albiflorin, paeoniflorin, liquiritin, isoliquiritin apioside, isoliquiritin, and glycyrrhizic acid in each part of SGD was determined by HPLC. In the animal experiment, mice were assigned into a normal group, a model group, a methotrexate group(0.001 g·kg~(-1)), and SGD, SGD sediment, SGD dialysate, and SGD-SAN groups of different doses(1, 2, and 4 g·kg~(-1)) respectively. The psoriasis grade of mice was evaluated based on the pathological changes of skin lesions, the content of inflammatory cytokines, organ index and other indicators. The results showed that SAN obtained by centrifugation at 13 000 r·min~(-1) for 30 min was stable after dialysis for 4 times, which were uniform spherical nanoparticles with the particle size of(164.43±1.34) nm, the polydispersity index of(0.28±0.05), and the Zeta potential of(-12.35±0.80) mV. The active compound content accounted for more than 70% of SGD. Compared with the model group, SAN and SGD decreased the skin lesion score, spleen index, and inflammatory cytokine levels(P<0.05 or P<0.01) and alleviated the skin thickening and infiltration of inflammatory cells. However, the sediment group and the dialysate group had no obvious effect. SGD showed a good therapeutic effect on imiquimod-induced psoriasis in mice, and SAN demonstrated the effect equivalent to SGD in a dose-dependent manner. Therefore, we conclude that the SAN formed during decocting is the main active form of SGD, which can lower the levels of inflammatory cytokines, promote the normal differentiation of keratinocytes, and reduce the infiltration of inflammatory cells in the treatment of psoriasis lesions in mice.


Asunto(s)
Medicamentos Herbarios Chinos , Ratones , Animales , Imiquimod , Medicamentos Herbarios Chinos/farmacología , Ácido Glicirrínico , Cromatografía Líquida de Alta Presión/métodos
7.
BMC Med ; 20(1): 408, 2022 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-36280870

RESUMEN

BACKGROUND: Dual inhibition of PD-1/PD-L1 and TGF-ß pathways is a rational therapeutic strategy for malignancies. SHR-1701 is a new bifunctional fusion protein composed of a monoclonal antibody against PD-L1 fused with the extracellular domain of TGF-ß receptor II. This first-in-human trial aimed to assess SHR-1701 in pretreated advanced solid tumors and find the population who could benefit from SHR-1701. METHODS: This was a dose-escalation, dose-expansion, and clinical-expansion phase 1 study. Dose escalation was initiated by accelerated titration (1 mg/kg q3w; intravenous infusion) and then switched to a 3+3 scheme (3, 10, 20, and 30 mg/kg q3w and 30 mg/kg q2w), followed by dose expansion at 10, 20, and 30 mg/kg q3w and 30 mg/kg q2w. The primary endpoints of the dose-escalation and dose-expansion parts were the maximum tolerated dose and recommended phase 2 dose. In the clinical-expansion part, selected tumors were enrolled to receive SHR-1701 at the recommended dose, with a primary endpoint of confirmed objective response rate (ORR). RESULTS: In total, 171 patients were enrolled (dose-escalation: n=17; dose-expansion, n=33; clinical-expansion, n=121). In the dose-escalation part, no dose-limiting toxicity was observed, and the maximum tolerated dose was not reached. SHR-1701 showed a linear dose-exposure relationship and the highest ORR at 30 mg/kg every 3 weeks, without obviously aggravated toxicities across doses in the dose-escalation and dose-expansion parts. Combined, 30 mg/kg every 3 weeks was determined as the recommended phase 2 dose. In the clinical-expansion part, SHR-1701 showed the most favorable efficacy in the gastric cancer cohort, with an ORR of 20.0% (7/35; 95% CI, 8.4-36.9) and a 12-month overall survival rate of 54.5% (95% CI, 29.5-73.9). Grade ≥3 treatment-related adverse events occurred in 37 of 171 patients (22%), mainly including increased gamma-glutamyltransferase (4%), increased aspartate aminotransferase (3%), anemia (3%), hyponatremia (3%), and rash (2%). Generally, patients with PD-L1 CPS ≥1 or pSMAD2 histochemical score ≥235 had numerically higher ORR. CONCLUSIONS: SHR-1701 showed an acceptable safety profile and encouraging antitumor activity in pretreated advanced solid tumors, especially in gastric cancer, establishing the foundation for further exploration. TRIAL REGISTRATION: ClinicalTrials.gov , NCT03710265.


Asunto(s)
Neoplasias Gástricas , Humanos , gamma-Glutamiltransferasa/uso terapéutico , Receptor de Muerte Celular Programada 1 , Anticuerpos Monoclonales/uso terapéutico , Aspartato Aminotransferasas/uso terapéutico , Factor de Crecimiento Transformador beta/uso terapéutico , Receptores de Factores de Crecimiento Transformadores beta/uso terapéutico
8.
Appl Microbiol Biotechnol ; 106(5-6): 1919-1932, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35179629

RESUMEN

Partially hydrolyzed konjac powder (PHKP) can be used to increase the daily intake of dietary fibers of consumers. To produce PHKP by enzymatic hydrolysis, a novel ß-mannanase gene (McMan5B) from Malbranchea cinnamomea was expressed in Pichia pastoris. It showed a low identity of less than 52% with other GH family 5 ß-mannanases. Through high cell density fermentation, the highest ß-mannanase activity of 42200 U mL-1 was obtained. McMan5B showed the maximal activity at pH 7.5 and 75 °C, respectively. It exhibited excellent pH stability and thermostability. Due to the different residues (Phe214, Pro253, and His328) in catalytic groove and the change of ß2-α2 loop, McMan5B showed unique hydrolysis property as compared to other ß-mannanases. The enzyme was employed to hydrolyze konjac powder for controllable production of PHKP with a weight-average molecular weight of 22000 Da (average degree of polymerization 136). Furthermore, the influence of PHKP (1.0%-4.0%) on the qualities of steamed bread was evaluated. The steamed bread adding 3.0% PHKP had the maximum specific volume and the minimum hardness, which showed 11.0% increment and 25.4% decrement as compared to the control, respectively. Thus, a suitable ß-mannanase for PHKP controllable production and a fiber supplement for steamed bread preparation were provided in this study. KEY POINTS: • A novel ß-mannanase gene (McMan5B) was cloned from Malbranchea cinnamomea and expressed in Pichia pastoris at high level. • McMan5B hydrolyzed konjac powder to yield partially hydrolyzed konjac powder (PHKP) instead of manno-oligosaccharides. • PHKP showed more positive effect on the quality of steamed bread than many other dietary fibers including konjac powder.


Asunto(s)
Amorphophallus , beta-Manosidasa , Amorphophallus/genética , Clonación Molecular , Concentración de Iones de Hidrógeno , Mananos/química , Onygenales , Pichia/genética , Polvos , beta-Manosidasa/química , beta-Manosidasa/genética
9.
BMC Vet Res ; 18(1): 143, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35439995

RESUMEN

BACKGROUND: Neuromedin U (NMU) plays an important role in activating the group 2 innate lymphoid cells (ILC2s) and initiating the host's anti-parasitic immune responses. It is aimed to explore the distribution characteristics of NMU in the sheep small intestine and the influence of Moniezia benedeni infection on them. In the present study, the pET-28a-NMU recombinant plasmids were constructed, and Escherichia coli. BL21 (DE3) were induced to express the recombinant protein. And then, the rabbit anti-sheep NMU polyclonal antibody was prepared and immunofluorescence staining was performed with it. The expression levels of NMU in the intestine of normal and Moniezia benedeni-infected sheep were detected by ELISA. RESULTS: The results showed that the molecular weight of the obtained NMU recombinant protein was consistent with the expected molecular (13 kDa) and it was expressed in the form of inclusion body. The titer and specificity of obtained rabbit anti-sheep NMU polyclonal antibody were good. The results of immunofluorescence analysis showed that the nerve fibers which specifically expressed NMU mainly extended from the ganglion in the submucosal to lamina propria (LP) in the sheep small intestine, and the expression level was relatively high; especially on the nerve fibers of LP around the intestinal glands. The expression levels were gradually increased from the duodenum to the ileum, and the levels in the jejunum and ileum were significantly higher than that in the duodenum (P < 0.05). In addition, scattered NMU positive cells were distributed in the epithelium of the jejunal crypts. Moniezia benedeni infection increased the expression of NMU in each intestinal segment, especially in the jejunum and ileum there were significant increase (P < 0.05). CONCLUSIONS: It was suggested that Moniezia benedeni infection could be detected by the high expression of NMU in sheep enteric nervous, and which laid the foundation for further studies on whether NMU exerts anti-parasitic immunity by activating ILC2s. In addition, NMU was expressed in some intestinal gland epitheliums, which also provided a basis for studying its roles in regulation of the immune homeostasis. The present study laid the foundation for further revealing the molecular mechanism of sheep's neural-immune interaction network perceiving the colacobiosis of parasites.


Asunto(s)
Cestodos , Inmunidad Innata , Animales , Inmunidad Innata/genética , Intestino Delgado , Linfocitos , Neuropéptidos , Conejos , Proteínas Recombinantes , Ovinos , Oveja Doméstica
10.
Biomed Chromatogr ; 36(2): e5252, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34591996

RESUMEN

Angelica sinensis (AS) is a common Traditional Chinese Medicine used for tonifying blood in China. Unprocessed AS and its four kinds of processed products (ASs) are used to treat blood deficiency syndrome in the country. The different blood-tonifying mechanisms of ASs remain unclear. In this work, a novel method integrating metabolomics and hematological and biochemical parameters was established to provide a complementary explanation of blood supplementation mechanism of ASs. Our results revealed that different ASs exhibited various blood supplementation effect, and that AS parched with alcohol demonstrated the best blood supplementation effect. Eight metabolites from liver tissue and 12 metabolites from spleen tissue were considered to be potential biomarkers. These biomarkers were involved in four metabolic pathways. Correlation analysis results showed that l-aspartic acid and l-alanine (spleen tissue), linoleic acid, and l-cystathionine (liver tissue) exhibited a high positive or negative correlation with the aforesaid biochemical indicators. The blood-supplementation effect mechanism of ASs were related to four metabolic pathways. l-Aspartic acid and l-alanine (spleen tissue), linoleic acid, and l-cystathionine (liver tissue) were the four key metabolites associated with the blood supplementation effect of ASs. This study gives a complementary explanation of the blood supplementation effect and mechanism of action of ASs.


Asunto(s)
Angelica sinensis/química , Medicamentos Herbarios Chinos/farmacología , Medicina Tradicional China , Metaboloma/efectos de los fármacos , Aminoácidos/metabolismo , Animales , Cromatografía de Gases y Espectrometría de Masas , Ácido Linoleico/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Metabolómica/métodos , Ratones , Bazo/efectos de los fármacos , Bazo/metabolismo
11.
Drug Chem Toxicol ; 45(3): 1119-1130, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-32842782

RESUMEN

Rhein is a key ingredient in many herbal remedies and is widely used. However, herbs containing rhein are frequently associated with poisoning incidents, especially in elderly subjects. Acute and subchronic toxicity of rhein in Kunming mice (KM) was investigated in this experiment. Acute toxicity tests showed a 40% lethality at a given rhein dose of 4000 mg/kg, and the LD50 of rhein was calculated by the bliss method to be greater than 2185.6 mg/kg. In subchronic toxicity, d-gal-induced aged and immature animals were randomized into three groups that were exposed to rhein of 0, 175, and 375 mg/kg/d for 75 days, respectively. No mortality was observed in immature mice group, whereas 55.5% (5/9) subjects in aged mice groups died in the high dosage group. AST, ALT, IL-6, TNF-α levels and typical histopathological changes indicate that rhein causes liver injury. In addition, our investigation explored possible hepatotoxic mechanisms of rhein and experimental results showed increased ROS production, NRF-2 and MDA levels and decreased SOD levels, demonstrating that rhein causes oxidative stress. MMP and mitochondrial swelling levels were able to assess the impact of rhein on mitochondrial function. Furthermore, the effect of rhein on apoptosis can be detected by flow cytometry. Our studies suggested that rhein induces oxidative stress leading to mitochondria dysfunction and apoptotic activation. Multidrug resistance protein (MRP) is an efflux transporter protein and is capable of transporting cellular oxidative stress-related substances. To further clarify the role of MRP in rhein induced oxidative stress, we examined MRP expression in the liver. However, the expression of MRP has no statistical significance.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Galactosa , Anciano , Animales , Antraquinonas/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Galactosa/metabolismo , Galactosa/farmacología , Humanos , Hígado , Ratones , Estrés Oxidativo
12.
Cancer Cell Int ; 21(1): 304, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-34112163

RESUMEN

BACKGROUND: Echinacoside (ECH) is the main active ingredient of Cistanches Herba, which is known to have therapeutic effects on metastatic tumors. However, the effects of ECH on liver cancer are still unclear. This study was to investigate the effects of ECH on the aggression of liver cancer cells. METHODS: Two types of liver cancer cells Huh7 and HepG2 were treated with different doses of ECH at different times and gradients. MTT and colony formation assays were used to determine the effects of ECH on the viability of Huh7 and HepG2 cells. Transwell assays and flow cytometry assays were used to detect the effects of ECH treatment on the invasion, migration, apoptosis and cell cycle of Huh7 and HepG2 cells. Western blot analysis was used to detect the effects of ECH on the expression levels of TGF-ß1, smad3, smad7, apoptosis-related proteins (Caspase-3, Caspase-8), and Cyto C in liver cancer cells. The relationship between miR-503-3p and TGF-ß1 was detected using bioinformatics analysis and Luciferase reporter assay. RESULTS: The results showed that ECH inhibited the proliferation, invasion and migration of Huh7 and HepG2 cells in a dose- and time-dependent manner. Moreover, we found that ECH caused Huh7 and HepG2 cell apoptosis by blocking cells in S phase. Furthermore, the expression of miR-503-3p was found to be reduced in liver tumor tissues, but ECH treatment increased the expression of miR-503-3p in Huh7 and HepG2 cells. In addition, we found that TGF-ß1 was identified as a potential target of miR-503-3p. ECH promoted the activation of the TGF-ß1/Smad signaling pathway and increased the expression levels of Bax/Bcl-2. Moreover, ECH could trigger the release of mitochondrial Cyto C, and cause the reaction Caspases grade. CONCLUSIONS: This study demonstrates that ECH exerts anti-tumor activity via the miR-503-3p/TGF-ß1/Smad aixs in liver cancer, and provides a safe and effective anti-tumor agent for liver cancer.

13.
Protein Expr Purif ; 178: 105779, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33115653

RESUMEN

Glucan branching enzymes (GBEs, EC 2.4.1.18) catalyze the formation of α-1,6-linked branch in starch, which is important for the starch modification with prospective properties. In this study, the aqGBE gene encoding an efficient glucan branching enzyme was cloned from Aquabacterium sp. strain A7-Y and successfully expressed in Escherichia coli BL21 (DE3). The specific activity of the purified recombinant enzyme rAqGBE was 2850 U/mg with potato starch as the optimal substrate, and the Km and Vmax values of rAqGBE were 1.18 mg/mL and 588.2 µmol/min/mg, respectively. Enzymological characterization showed that rAqGBE exhibits its optimal activity under the condition of 40 °C and pH 7.0, respectively, which is independent of calcium ions. Otherwise, rAqGBE-treated potato starch showed different chain length distribution compared with control, the numbers of short chains (degree of polymerization, DP < 7) and long chains (DP > 25) increased from 4.5% to 9.6% and 6.1%-15.7% after enzymatic treatment, respectively. In starch anti-ageing assay, with minimum usage of 0.8 mg rAqGBE per g starch, the rAqGBE-treated potato starch exhibited reduced retrogradation properties. Our results indicate that the branching enzyme AqGBE may therefore be a promising tool for the enzymatic modification of starch.


Asunto(s)
Enzima Ramificadora de 1,4-alfa-Glucano , Proteínas Bacterianas , Burkholderiales/genética , Almidón/química , Enzima Ramificadora de 1,4-alfa-Glucano/biosíntesis , Enzima Ramificadora de 1,4-alfa-Glucano/química , Enzima Ramificadora de 1,4-alfa-Glucano/genética , Enzima Ramificadora de 1,4-alfa-Glucano/aislamiento & purificación , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Burkholderiales/enzimología , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación
14.
J Cosmet Laser Ther ; 23(5-6): 137-141, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35038956

RESUMEN

(a) To evaluate the efficacy and safety of narrow-band intense-pulsed light (DPL) in immediate post-operative scar. (b) To observe the process of scar formation under dermoscopy in the first 6 months. Nine patients with postoperative scars were enrolled in the randomized, prospective, split-scar study. Patients were treated in one half of the scar with DPL for cosmetic improvement at a wavelength of 500-600 nm and the other half was not treated as control. The laser treatments were initiated 2 weeks after the surgery and were given 3 times over a 4-week period. All patients were followed-up for 3 months from the last treatment. Photographs and dermoscopy digital images were collected each time. (a) Neither DPL or control produce statistically significant improvements in Vancouver Scar Scale. Moreover, comparatively, there was no statistical difference in Vancouver Scar Scale between DPL or control. However, 6 out of 9 patients treated with DPL had reduced scores in vascularity sooner compared with control. (b) Under dermoscopy, redness, and swelling were obvious from 2 weeks after surgery, but were gradually alleviated. The surface of the scar gradually became uneven and rough. DPL might be beneficial in early recovery of immediate post-operative scar.


Asunto(s)
Cicatriz , Terapia por Luz de Baja Intensidad , Cicatriz/etiología , Cicatriz/patología , Cicatriz/radioterapia , Dermoscopía , Eritema , Humanos , Terapia por Luz de Baja Intensidad/efectos adversos , Terapia por Luz de Baja Intensidad/métodos , Estudios Prospectivos , Resultado del Tratamiento
15.
Pak J Med Sci ; 37(7): 1989-1993, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34912431

RESUMEN

OBJECTIVES: To investigate the efficacy and postoperative complications of lattice carbon dioxide laser in the treatment of postmenopausal patients with mild to moderate stress urinary incontinence. METHODS: A total of 30 postmenopausal female patients with mild to moderate stress urinary incontinence, recruited from the Affiliated Hospital of Hebei University from September to November 2019, were selected as the study subjects and treated with lattice carbon dioxide laser therapy. Treatment was given at intervals of one month. The degree of urinary incontinence, the urinary incontinence questionnaire (ICI-Q-SF) score, and the urinary incontinence quality of life scale (I-QOL)) Score, surgical satisfaction, one hour pad test and postoperative complications before treatment and after each treatment of all patients were respectively recorded and compared. RESULTS: Compared with those before treatment, the grade of urinary incontinence and ICI-Q-SF scores of these 30 patients after each treatment were lower, and their I-QOL scores were higher. The difference of one hour urine pad test was statistically significant (P<0.05), but the follow-up data of three months after the third treatment was close to that of one month after the first treatment. The satisfaction rate of these 30 patients was 76.67% (23/30). After treatment, only one patient presented vaginal itching discomfort on the first day after surgery and the symptoms disappeared three days later. No obvious complications occurred in the other 29 patients. CONCLUSION: The treatment of mild and moderate postmenopausal patients with stress urinary incontinence with lattice carbon dioxide laser can effectively reduce the incidence of incontinence and improve the quality of life.

16.
J Am Chem Soc ; 142(22): 9966-9974, 2020 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-32363869

RESUMEN

The first example of free amine γ-C(sp3)-H fluorination is realized using 2-hydroxynicotinaldehyde as the transient directing group. A wide range of cyclohexyl and linear aliphatic amines could be fluorinated selectively at the γ-methyl and methylene positions. Electron withdrawing 3,5-disubstituted pyridone ligands were identified to facilitate this reaction. Computational studies suggest that the turnover determining step is likely the oxidative addition step for methylene fluorination, while it is likely the C-H activation step for methyl fluorination. The explicit participation of Ag results in a lower energetic span for methylene fluorination and a higher energetic span for methyl fluorination, which is consistent with the experimental observation that the addition of silver salt is desirable for methylene but not for methyl fluorination. Kinetic studies on methyl fluorination suggest that the substrate and PdL are involved in the rate-determining step, indicating that the C-H activation step may be partially rate-determining. Importantly, an energetically preferred pathway has identified an interesting pyridone-assisted bimetallic transition state for the oxidative addition step in methylene fluorination, thus uncovering a potential new role of the pyridone ligand.


Asunto(s)
Aminas/química , Hidrocarburos Fluorados/síntesis química , Paladio/química , Catálisis , Halogenación , Hidrocarburos Fluorados/química , Estructura Molecular
17.
J Cardiovasc Electrophysiol ; 31(6): 1307-1314, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32250512

RESUMEN

BACKGROUND: The safety and efficacy of superior vena cava (SVC) isolation using second-generation cryoballoon (CB) ablation remain unknown. METHODS: A total of 26 (3.2%) patients with SVC-related paroxysmal atrial fibrillation (AF) from a consecutive series of 806 patients who underwent second-generation CB were included. Pulmonary vein isolation was initially achieved by CB ablation. If the SVC trigger was determined, the electrical isolation of SVC isolation was performed using the second-generation CB. RESULTS: Real-time SVC potential was observed in all patients. Isolation of the SVC was successfully accomplished in 21 (80.8%) patients. The mean number of freeze cycles in each patient was 2.1 ± 1.1. The mean time to isolation and ablation duration were 22.5 ± 14.2 seconds and 94.5 ± 22.3 seconds, respectively. A transient phrenic nerve (PN) injury was observed in five patients (19.2%). There were two patients (7.7%) experienced reversible sinus node injury during the first application. During a mean follow-up period of 13.2 ± 5.8 months, four patients (15.4%) had atrial arrhythmia recurrences. CONCLUSION: Isolation of SVC using the second-generation 28-mm CB is feasible when SVC driver during AF is identified. Vigilant monitoring of PN function during CB ablation of SVC is needed to avoid PN injury.


Asunto(s)
Fibrilación Atrial/cirugía , Catéteres Cardíacos , Criocirugía/instrumentación , Vena Cava Superior/cirugía , Potenciales de Acción , Anciano , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Criocirugía/efectos adversos , Diseño de Equipo , Femenino , Lesiones Cardíacas/etiología , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Traumatismos de los Nervios Periféricos/etiología , Nervio Frénico/lesiones , Recurrencia , Estudios Retrospectivos , Nodo Sinoatrial/lesiones , Factores de Tiempo , Resultado del Tratamiento , Vena Cava Superior/diagnóstico por imagen , Vena Cava Superior/fisiopatología
18.
Sensors (Basel) ; 20(3)2020 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-32045985

RESUMEN

Multi-radio technology is regarded as a promising way to improve the performance of Wireless Sensor Networks (WSNs) and has attracted much attention of researchers. It is very important to reduce energy consumption and to prolong the lifetime of Multi-Radio WSNs (MR-WSNs), since the node is generally battery-operated in MR-WSN environments. In this paper, two typical types of energy consumption process, the transmitting energy consumption and idle listening energy consumption, are analyzed firstly. Based on the above analysis, the energy consumption model of multi-radio nodes is built, and then it is considered as the optimization objective for the minimization energy consumption of multi-radio nodes. Furthermore, the heuristic optimal energy consumption task scheduling strategy based on the Particle Swarm Optimization (PSO) algorithm is proposed, and then the detailed steps of the proposed strategy are presented. Finally, the effectiveness and performance of the proposed strategy are evaluated through practical experiments and simulations. Evaluation results show that the proposed strategy outperforms some other algorithms, in terms of energy consumption, network lifetime, and tasks extensibility.

19.
J Asian Nat Prod Res ; 22(7): 639-646, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31056992

RESUMEN

Two new compounds 6,7-dimethoxy-2-[2-(2'-hydroxyphenyl)ethyl]chromone (1) and 6,7-dimethoxy-2-[2-(4'-hydroxyphenyl)ethenyl]chromone (2), together with ten known 2-(2-phenylethyl)chromones (3-12) were isolated from the resinous wood of Aquilaria sinensis (Lour.) Gilg. Their structures were elucidated by detailed IR, MS, NMR spectroscopic analyses, and comparison with reported. The absolute configuration of 3 was confirmed by Cu Kα X-ray crystallographic experiment, and the X-ray crystallographic data of 3 were firstly reported. Compounds 2, 8, 10, and 11 exhibited strong ABTS•+ radical scavenging activity, with IC50 values of 12.3, 16.5, 12.1, and 34.7 µM, respectively.[Formula: see text].


Asunto(s)
Cromonas , Thymelaeaceae , Flavonoides , Estructura Molecular
20.
J Nurs Manag ; 28(2): 199-208, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31811782

RESUMEN

AIMS: To review the studies on nursing research capacity and the managerial approaches that have been taken to promote nursing research capacity building in China. BACKGROUND: In the nursing profession, research has become increasingly important worldwide. Over the last two decades, continuous efforts have been devoted to improving nursing research capacity in China. However, the results of these efforts were rarely evaluated in a national scale. EVALUATION: A systematic literature review was conducted in accordance with the PRISMA checklist and guidelines. The literature was sourced from PubMed, CINAHL and two Chinese databases. In total, 19 articles were selected and their results were integrated, compared and analysed. KEY ISSUES: The development of nursing research has become a recent phenomenon in China. Chinese nurses' perceptions regarding research were mostly positive. However, their participation in research activity has traditionally been minimal. The factors associated with nursing research capacity in China were nurses' personal characteristics and organisational contexts. Several effective strategies (e.g. on-the-job research education) have been used to promote nursing research capacity. CONCLUSION: Currently, nursing research capacity in China is low despite hospital-promoting efforts. Systematic approaches need to be implemented to increase nursing research capacity in China in the near future. IMPLICATIONS FOR NURSING MANAGEMENT: Nursing administrators need to seek innovative strategies to resolve issues (e.g. lack of research time and limited nursing research resources). They also need to strengthen their leadership skills in order to achieve the above objectives.


Asunto(s)
Investigación en Enfermería/métodos , Investigación/tendencias , China , Humanos , Liderazgo , Investigación en Enfermería/tendencias
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