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1.
Chemistry ; : e202401400, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38736421

RESUMEN

Coumestan represents a biologically relevant structural motif distributed in a number of natural products, and the rapid construction of related derivatives as well as the characterization of targets would accelerate lead compound discovery in medicinal chemistry. In this work, a general and scalable approach to 8,9-dihydroxycoumestans via two-electrode constant current electrolysis was developed. The application of a two-phase (aqueous/organic) system plays a crucial role for success, protecting the sensitive o-benzoquinone intermediates from over-oxidation. Based on the structurally diverse products, a primary SAR study on coumestan scaffold was completed, and compound 3 r exhibited potent antiproliferative activities and a robust topoisomerase I (Top1) inhibitory activity. Further mechanism studies demonstrates that compound 3 r was a novel Top1 poison, which might open an avenue for the development of Top1-targeted antitumor agent.

2.
Biochem Biophys Res Commun ; 639: 91-99, 2023 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-36476951

RESUMEN

The Transmembrane Carboxyl Terminal Domain (TMD) of some Bcl-2 family proteins has been demonstrated to play a key role in modulating apoptosis. We here ustilzed live-cell fluorescence imaging to evaluate how the Bcl-xL TMD (XT) regulate apoptosis. Cell viability assay revealed that XT had strong anti-apoptotic ability similarly to the full-length Bcl-xL. Fluorescence images of living cells co-expressing CFP-XT and Bad-YFP or YFP-Bax revealed that XT recruited Bad to mitochondria but prevented Bax translocation to mitochondria, and also significantly suppressed Bad/Bax-mediated apoptosis, indicating that XT prevents the pro-apoptotic function of Bad and Bax. Fluorescence Resonance Energy Transfer (FRET) analyses determined that XT directly interacted with Bad and Bax, and deletion of XT completely eliminated the mitochondrial localization and homo-oligomerization of Bcl-xL. Fluorescence images of living cells co-expressing CFP-XT and YFP-Bax revealed that XT significantly prevented mitochondrial Bax oligomerization, resulting in cytosolic Bax distribution. Collectively, XT is necessary for the mitochondrial localization and anti-apoptotic capacity of Bcl-xL, and XT, similarly to the full-length Bcl-xL, forms homo-oligomers on mitochondria to directly interact with Bad and Bax to inhibit their apoptotic functions.


Asunto(s)
Mitocondrias , Proteínas Proto-Oncogénicas c-bcl-2 , Proteína bcl-X/metabolismo , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Mitocondrias/metabolismo , Apoptosis/fisiología
3.
Opt Express ; 31(26): 43764-43770, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38178465

RESUMEN

We recently developed a SCC-FRET (single-cell-based calibration of a FRET system) method to quantify spectral crosstalk correction parameters (ß and δ) and system calibration parameters (G and k) of a Förster resonance energy transfer (FRET) system by imaging a single cell expressing a standard FRET plasmid with known FRET efficiency (E) and donor-acceptor concentration ratio (RC) (Liu et al., Opt. Express30, 29063 (2022)10.1364/OE.459861). Here we improved the SCC-FRET method (named as Im-SCC-FRET) to simultaneously obtain ß, δ, G, k and the acceptor-to-donor extinction coefficient ratio (ε A ε D), which is a key parameter to calculate the acceptor-centric FRET efficiency (EA), of a FRET system when the range of ß and δ values is set as 0-1. In Im-SCC-FRET, the target function is changed from the sum of absolute values to the sum of squares according to the least squares method, and the initial value of ß and δ estimated by the integral but not the maximum value spectral overlap between fluorophore and filter. Compared with SCC-FRET, the experimental results demonstrate that Im-SCC-FRET can obtain more accurate and stable results for ß, δ, G, and k, and add the ratio ε A ε D, which is necessary for the FRET hybrid assay. Im-SCC-FRET reduces the complexity of experiment preparation and opens up a promising avenue for developing an intelligent FRET correction system.

4.
Opt Express ; 31(2): 1787-1798, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36785206

RESUMEN

Pure-quartic solitons (PQSs) are gradually becoming a hotspot in recent years due to their potential advantage to achieve high energy. Meanwhile, the fundamental research of PQSs is still in the fancy stage, and exploring soliton dynamics can promote the development of PQSs. Herein, we comprehensively and numerically investigate the impact of saturation power, small-signal gain, and output coupler on PQS dynamics in passively mode-locked fiber lasers. The result indicates that altering the above parameters makes PQSs exhibit pulsating or creeping dynamics similar to traditional solitons. Moreover, introducing an intra-cavity filter combined with intra-cavity large fourth-order dispersion makes PQSs go through stationary, pulsating to erupting. That is, the intra-cavity filter changes PQS dynamics. These findings provide new insights into PQS dynamics in fiber lasers.

5.
Strahlenther Onkol ; 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37603050

RESUMEN

PURPOSE: The goal of this study was to propose a knowledge-based planning system which could automatically design plans for lung cancer patients treated with intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: From May 2018 to June 2020, 612 IMRT treatment plans of lung cancer patients were retrospectively selected to construct a planning database. Knowledge-based planning (KBP) architecture named αDiar was proposed in this study. It consisted of two parts separated by a firewall. One was the in-hospital workstation, and the other was the search engine in the cloud. Based on our previous study, A­Net in the in-hospital workstation was used to generate predicted virtual dose images. A search engine including a three-dimensional convolutional neural network (3D CNN) was constructed to derive the feature vectors of dose images. By comparing the similarity of the features between virtual dose images and the clinical dose images in the database, the most similar feature was found. The optimization parameters (OPs) of the treatment plan corresponding to the most similar feature were assigned to the new plan, and the design of a new treatment plan was automatically completed. After αDiar was developed, we performed two studies. The first retrospective study was conducted to validate whether this architecture was qualified for clinical practice and involved 96 patients. The second comparative study was performed to investigate whether αDiar could assist dosimetrists in improving the quality of planning for the patients. Two dosimetrists were involved and designed plans for only one trial with and without αDiar; 26 patients were involved in this study. RESULTS: The first study showed that about 54% (52/96) of the automatically generated plans would achieve the dosimetric constraints of the Radiation Therapy Oncology Group (RTOG) and about 93% (89/96) of the automatically generated plans would achieve the dosimetric constraints of the National Comprehensive Cancer Network (NCCN). The second study showed that the quality of treatment planning designed by junior dosimetrists was improved with the help of αDiar. CONCLUSIONS: Our results showed that αDiar was an effective tool to improve planning quality. Over half of the patients' plans could be designed automatically. For the remaining patients, although the automatically designed plans did not fully meet the clinical requirements, their quality was also better than that of manual plans.

6.
Epilepsia ; 64(10): 2667-2678, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37522416

RESUMEN

OBJECTIVE: Bone metabolism can be influenced by a range of factors. We selected children with self-limited epilepsy with centrotemporal spikes (SeLECTS) and lifestyles similar to those of healthy children to control for the confounding factors that may influence bone metabolism. We aimed to identify the specific effects of epilepsy and/or anti-seizure medications (ASMs) on bone metabolism. METHODS: Patients with SeLECTS were divided into an untreated group and a monotherapy group, and the third group was a healthy control group. We determined the levels of various biochemical markers of bone metabolism, including procollagen type I nitrogenous propeptide (PINP), alkaline phosphatase (ALP), osteocalcin (OC), collagen type I cross-linked C-telopeptide (CTX), calcium, magnesium, phosphorus, parathyroid hormone (PTH), and vitamin D3 (VD3 ). RESULTS: A total of 1487 patients (from 19 centers) were diagnosed with SeLECTS; 1032 were analyzed, including 117 patients who did not receive any ASMs (untreated group), 643 patients who received only one ASM (monotherapy group), and 272 children in the healthy control group. Except for VD3 , other bone metabolism of the three groups were different (p < .001). Bone metabolism was significantly lower in the untreated group than the healthy control group (p < .05). There were significant differences between the monotherapy and healthy control group in the level of many markers. However, when comparing the monotherapy and untreated groups, the results were different; oxcarbazepine, levetiracetam, and topiramate had no significant effect on bone metabolism. Phosphorus and magnesium were significantly lower in the valproic acid group than the untreated group (adjusted p < .05, Cliff's delta .282-.768). CTX was significantly higher in the lamotrigine group than in the untreated group (adjusted p = .012, Cliff's delta = .316). SIGNIFICANCE: Epilepsy can affect many aspects of bone metabolism. After controlling epilepsy and other confounders that affect bone metabolism, we found that the effects of ASMs on bone metabolism differed. Oxcarbazepine, levetiracetam, and topiramate did not affect bone metabolism, and lamotrigine corrected some of the abnormal markers of bone metabolism in patients with epilepsy.

7.
Org Biomol Chem ; 21(27): 5643-5647, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37377436

RESUMEN

Alkyltin fluoride is a frequently used electrophilic stannylation reagent via the cleavage of the Sn-F bond in traditional organic synthetic chemistry. Herein, we report the unprecedented copper-catalyzed aminoalkylation of maleimides using alkyltin fluoride as alkylating reagent through cleavage of the C-Sn bond via a radical pathway. Excellent functional group tolerance, use of O2 as green oxidant and late-stage modification of some drug intermediates are the standout features of the current toolbox. Mechanistic studies reveal that alkyltin fluorides are capable of producing alkyl radicals in a Cu/O2 catalytic system.

8.
Nature ; 545(7652): 80-83, 2017 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-28379942

RESUMEN

It is not easy to fabricate materials that exhibit their theoretical 'ideal' strength. Most methods of producing stronger materials are based on controlling defects to impede the motion of dislocations, but such methods have their limitations. For example, industrial single-phase nanocrystalline alloys and single-phase metallic glasses can be very strong, but they typically soften at relatively low strains (less than two per cent) because of, respectively, the reverse Hall-Petch effect and shear-band formation. Here we describe an approach that combines the strengthening benefits of nanocrystallinity with those of amorphization to produce a dual-phase material that exhibits near-ideal strength at room temperature and without sample size effects. Our magnesium-alloy system consists of nanocrystalline cores embedded in amorphous glassy shells, and the strength of the resulting dual-phase material is a near-ideal 3.3 gigapascals-making this the strongest magnesium-alloy thin film yet achieved. We propose a mechanism, supported by constitutive modelling, in which the crystalline phase (consisting of almost-dislocation-free grains of around six nanometres in diameter) blocks the propagation of localized shear bands when under strain; moreover, within any shear bands that do appear, embedded crystalline grains divide and rotate, contributing to hardening and countering the softening effect of the shear band.

9.
Molecules ; 28(11)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37298944

RESUMEN

Versatile and concise Pd-catalyzed oxidative N-alkenylation of N-aryl phosphoramidates with alkenes is described in this study, a reaction that is of great significance but surprisingly unexploited. The transformation proceeds under mild reaction conditions, using O2 as a green oxidant and TBAB as an effective additive. An efficient catalytic system allows a variety of drug-related substrates to participate in these transformations, which is of great interest in the drug discovery and development of phosphoramidates.


Asunto(s)
Alquenos , Paladio , Aminación , Estructura Molecular , Catálisis
10.
Opt Express ; 30(16): 29063-29073, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36299090

RESUMEN

Reliable measurements of calibration parameters are crucial for quantitative three-cube Förster resonance energy transfer (FRET) measurements. Here we have developed a single-cell-based calibration method (SCC-FRET), which can simultaneously obtain spectral crosstalk correction parameters (ß and δ) and calibration parameters (G and k) of a quantitative FRET system by imaging a cell expressing one kind of standard FRET plasmid with a known FRET efficiency (E) and the donor-to-acceptor concentration ratio (RC). We performed the SCC-FRET method on a three-cube FRET microscopy for the cells expressing C5V, and obtained ß = 0.150 ± 0.000, δ = 0.610 ± 0.000, G = 2.840 ± 0.065, and k = 0.847 ± 0.013. These parameters were used to measure the E and RC values of C17V and C32V constructs in living cells and obtained EC17V = 0.382 ± 0.010 and EC32V = 0.311 ± 0.007, RC17V = 1.010 ± 0.023 and RC32V = 1.050 ± 0.022, consistent with the reported values, demonstrating the effectiveness of the the SCC-FRET method. We also performed the SCC-FRET method for the cells with different S/N levels (S/N > 10, 10 > S/N > 3, 3 > S/N > 1, respectively), and obtained consistent system calibration parameters under different S/N levels, indicating excellent robustness. SCC-FRET requires only imaging a cell expressing one kind of standard FRET plasmid for measuring all calibration parameters under identical imaging conditions, rendering the SCC-FRET method extremely convenient, accurate, and robust. The SCC-FRET provides strong support for expanding the biological application of quantitative FRET analysis in living cells.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Microscopía , Transferencia Resonante de Energía de Fluorescencia/métodos , Calibración , Fenómenos Fisiológicos Celulares
11.
Eur Radiol ; 32(6): 4046-4055, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35066633

RESUMEN

OBJECTIVES: To evaluate the diagnostic value of computer-aided diagnosis (CAD) software on ultrasound in distinguishing benign and malignant breast masses and avoiding unnecessary biopsy. METHODS: This prospective, multicenter study included patients who were scheduled for pathological diagnosis of breast masses between April 2019 and November 2020. Ultrasound images, videos, CAD analysis, and BI-RADS were obtained. The AUC, accuracy, sensitivity, specificity, PPV, and NPV were calculated and compared with radiologists. RESULTS: Overall, 901 breast masses in 901 patients were enrolled in this study. The accuracy, sensitivity, specificity, PPV and NPV of CAD software were 89.6%, 94.2%, 87.0%, 80.4%, and 96.3, respectively, in the long-axis section; 89.0%, 91.4%, 87.7%, 80.8%, and 94.7%, respectively, in the short-axis section. With BI-RADS 4a as the cut-off value, CAD software has a higher AUC (0.906 vs 0.734 vs 0.696, all p < 0.001) than both experienced and less experienced radiologists. With BI-RADS 4b as the cut-off value, CAD software showed better AUC than less experienced radiologists (0.906 vs 0.874, p < 0.001), but not superior to experienced radiologists (0.906 vs 0.883, p = 0.057). After the application of CAD software, the unnecessary biopsy rate of BI-RADS categories 4 and 5 was significantly decreased (33.0% vs 11.9%, 37.8% vs 14.5%), and the malignant rate of biopsy in category 4a was significantly increased (11.6% vs 40.7%, 7.4% vs 34.9%, all p < 0.001). CONCLUSIONS: CAD software on ultrasound can be used as an effective auxiliary diagnostic tool for differential diagnosis of benign and malignant breast masses and reducing unnecessary biopsy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03887598) KEY POINTS: • Prospective multicenter study showed that computer-aided diagnosis software provides greater diagnostic confidence for differentiating benign and malignant breast masses. • Computer-aided diagnosis software can help radiologists reduce unnecessary biopsy. • The management of patients with breast masses becomes more appropriate.


Asunto(s)
Neoplasias de la Mama , Mama , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Computadores , Diagnóstico por Computador/métodos , Femenino , Humanos , Estudios Prospectivos , Sensibilidad y Especificidad , Ultrasonografía Mamaria/métodos
12.
Phys Chem Chem Phys ; 24(38): 23737-23748, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36156614

RESUMEN

Na-, K- and Mg-ion batteries (NIBs, KIBs and MIBs) have drawn considerable interest due to their high abundance and excellent safety. However, the lack of high-performance anode materials is a major obstacle to its development. A metallic SnB planar monolayer is predicted by using the two-dimensional global minimum structure search method of swarm intelligence. Based on first-principles calculations, we proved that the metal SnB monolayer has high binding energy and excellent dynamical, thermal and mechanical stability. It is worth noting that the SnB monolayer has several stable adsorption sites for Na-, K- and Mg-ions, so it has a high theoretical capacity of 620.93, 517.44 and 620.93 mA h g-1, respectively. For Na-, K- and Mg-ion batteries, the low diffusion barriers of the SnB monolayer are 0.22, 0.07 and 0.68 eV, and the low average open circuit voltages are 0.42, 0.49 and 0.23 V, which ensure long service life and fast charging in practical applications. In addition, it is proved that the SnB monolayer maintains excellent conductivity and stability during the charge-discharge process. The results show that the SnB monolayer offers innovative advantages for the development of new two-dimensional planar structures that further advance the development of anode materials for metal ion batteries.

13.
Ann Clin Microbiol Antimicrob ; 21(1): 25, 2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35681153

RESUMEN

BACKGROUND: GeneXpert enterovirus Assay is a PCR-based assay for Enterovirus meningitis diagnosis. However, there is currently no research about the performance of GeneXpert enterovirus assay in the diagnosis of enterovirus meningitis. Thus, a systematic review and meta-analysis is significant on the topic. METHODS: Embase, Cochrane Library, Web of Science, and PubMed were systematically reviewed with retrieval types. Some criteria were used to filter the studies. Only studies published in English, that made a comparison between GeneXpert enterovirus assay and RT-PCR, and could be formulated in a 2*2 table, were included. The quality of the included studies was evaluated by QUADAS-2. The effect of the GeneXpert enterovirus assay was assessed by the Sensitivity, Specificity, Positive Likelihood Ratio, Negative Likelihood Ratio, Diagnosis Odds Ratio, and summary receiver operating characteristic (SROC) curve. Publication bias and heterogeneity were evaluated by the Deeks' funnel test and Bivariate Box plot respectively. RESULTS: 7 studies were recruited in the analysis. The Pooled Sensitivity was 0.96 [95% CI (0.94-0.97)], Pooled Specificity was 0.99 [95% CI (0.98-0.99)], Positive Likelihood Ratio was 130.46 [95% CI (35.79-475.58)], Negative Likelihood Ratio was 0.04 [95% CI (0.02-0.10)], and Diagnostic Odds Ratio was 3648.23 (95% CI [963.99-13,806.72)]. In SROC Curve, Area Under Curve (AUC) was 0.9980, and Q*= 0.9849. In Deeks' funnel test, the P-value was 0.807 (P > 0.05), indicating no publication bias. The Bivariate Box plot indicated no evident heterogeneity. CONCLUSIONS: The GeneXpert enterovirus assay demonstrated high diagnostic accuracy in diagnosing enterovirus meningitis.


Asunto(s)
Meningitis , Humanos , Curva ROC , Sensibilidad y Especificidad
14.
Can J Physiol Pharmacol ; 100(1): 26-34, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34411489

RESUMEN

Diabetic nephropathy (DN) is the most common complication of diabetic patients, and has become a global healthcare problem. In this study, we used diabetic mice to evaluate the effect of Losartan on DN, in which the experimental animals were divided into three groups: non-diabetic mice (db/m group), untreated-diabetic mice (db/db group), and Losartan-treated diabetic mice (db/db-losartan). Next, immunohistochemistry and immunofluorescence were used to detect Wilms tumor protein 1 (WT-1) and synaptopodin expression, respectively. Protein levels of WT-1, synaptopodin, claudin1, and Pax-2 were assessed by Western blotting and real-time PCR. The miR-193a mRNA levels were quantitated by real-time PCR. The results showed that albuminuria was increased in diabetic mice compared with control animals and was significantly ameliorated by treatment with Losartan. In addition, Losartan significantly upregulated the immunopositive cell numbers of WT-1, the expression of WT-1 and synaptopodin in renal tissue. By contrast, expression of claudin1 and Pax-2 in renal tissue were decreased in db/db-losartan group. Besides, expression of miR-193a was decreased significantly in db/db-losartan group compared with the untreated diabetic group. Thus, Losartan has renoprotective effects on the control of tissue damage possibly by inhibiting the expression of miR-193a, thereby promoting the repair of podocyte injury in mice with DN.


Asunto(s)
Retinopatía Diabética/genética , Retinopatía Diabética/prevención & control , Expresión Génica/efectos de los fármacos , Losartán/farmacología , Losartán/uso terapéutico , MicroARNs/genética , MicroARNs/fisiología , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Proteínas WT1/genética , Proteínas WT1/metabolismo , Adulto , Anciano , Albuminuria/etiología , Albuminuria/genética , Albuminuria/prevención & control , Animales , Retinopatía Diabética/etiología , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Sustancias Protectoras , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
15.
Allergy Asthma Proc ; 43(2): 124-132, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35317889

RESUMEN

Background: Immunoglobulin E (IgE) plays an important role in asthma, but a few patients exhibit extremely high levels of serum total IgE. Objective: This study aimed to investigate the profiles of comorbidity and/or complications, severity, and sensitizations in patients with asthma and with a total IgE level > 1000 kU/L. Methods: We retrospectively analyzed 170 patients with asthma and with total IgE levels of >1000 kU/L from the inpatient data base. Available information, including age, gender, body mass index, diagnosis, results of routine blood tests, pulmonary function, fractional exhaled nitric oxide, induced sputum (if any), IgE (both total and specific) tests and medication records were analyzed. Results: In the study subjects, >80% were adults, and the average total IgE level was median (interquartile range) 1438 kU/L (1181-2255 kU/L). Approximately 15% of the subjects had at least one comorbidity and/or complication, and 78.82% of the subjects were positive for at least one allergen. Airway infections (44.71%) and rhinosinusitis (41.18%) accounted for the two most common conditions despite age groups. Total IgE levels did not differ among the subjects with different conditions. Overall, mites had the highest positive rate (59.4%). Serum total IgE levels were positively correlated with house-dust mite specific IgE (sIgE) levels (r = 0.23; p < 0.05), peripheral blood eosinophil counts (r = 0.21; p < 0.01), and the number of confirmed sIgE positivity (r = 0.19; p < 0.01), and optimal scaling analysis showed that asthma severity was associated with Aspergillus fumigatus sIgE levels. Conclusion: In the subjects with asthma and with a total IgE level of >1000 kU/L, the two most common conditions were airway infections and rhinosinusitis, despite sensitization. A. fumigatus sIgE levels were closely associated with total IgE levels and asthma severity.


Asunto(s)
Asma , Inmunoglobulina E , Adulto , Alérgenos , Asma/diagnóstico , Asma/epidemiología , Comorbilidad , Humanos , Estudios Retrospectivos
16.
Cytometry A ; 99(11): 1091-1101, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33843148

RESUMEN

Molecular regulatory network among the B cell leukemia-2 (Bcl-2) family proteins is a research hotspot on apoptosis. The inhibitory priority of anti-apoptotic Bcl-2 family proteins (such as Bcl-xL) to pro-apoptotic Bcl-2 family proteins (such as Bad, tBid and Bax) determines the outcome of their interactions. Based on over-expression model system, we here evaluate the inhibitory priority of Bcl-xL to Bad, tBid and Bax by using live-cell imaging assay on cell viability. Fluorescence images of living cells co-expressing CFP-Bcl-xL and YFP-Bad or YFP-tBid or YFP-Bax showed that Bcl-xL markedly inhibited Bad/tBid/Bax-mediated apoptosis, revealing that Bcl-xL inhibits the proapoptotic function of Bad, tBid and Bax. In the case of equimolar co-expression of Bad and CFP-Bcl-xL, the inhibition of Bcl-xL on tBid/Bax mediate-apoptosis was completely relieved. Moreover, co-expression of tBid-P2A-CFP-Bcl-xL significantly relieved the inhibition of Bcl-xL on the pro-apoptotic ability Bax, suggesting that Bcl-xL preferentially inhibits the pro-apoptotic ability of Bad over tBid, subsequently to Bax.


Asunto(s)
Apoptosis , Proteínas Proto-Oncogénicas c-bcl-2 , Supervivencia Celular , Proteína X Asociada a bcl-2/genética , Proteína bcl-X/genética
17.
Eur Radiol ; 31(7): 5012-5020, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33409788

RESUMEN

OBJECTIVES: To evaluate for the first time the performance of a deep learning method based on no-new-Net for fully automated segmentation and volumetric measurements of intracerebral hemorrhage (ICH), intraventricular extension of intracerebral hemorrhage (IVH), and perihematomal edema (PHE) in primary ICH on CT. METHODS: Three hundred and eighty primary ICH patients who underwent CT at hospital arrival were divided into a training cohort (n = 300) and a validation cohort (n = 80). An independent cohort with 80 patients was used for testing. Ground truth (segmentation masks) was manually generated by radiologists. Model performance on lesion segmentation and volumetric measurement of ICH, IVH, and PHE were evaluated by comparing the model results with the segmentations performed by radiologists. RESULTS: In the test cohort, the Dice scores of lesion segmentation were 0.92, 0.79, and 0.71 for ICH, IVH, and PHE, respectively. The sensitivities were 0.93 for ICH, 0.88 for IVH, and 0.81 for PHE. The positive predictive values were 0.92, 0.76, and 0.69 for ICH, IVH, and PHE, respectively. Excellent concordance (concordance correlation coefficients [CCCs] ≥ 0.98) of ICH and IVH and good concordance of PHE (CCCs ≥ 0.92) were demonstrated between manually and automatically measured volumes. The model took approximately 15 s to provide automatic segmentation and volume analysis for each patient. CONCLUSION: Our model demonstrates good reliability for automatic segmentation and volume measurement of ICH, IVH, and PHE in primary ICH, which can be useful to reduce the effort and time of doctors to calculate volumes of ICH, IVH, and PHE. KEY POINTS: • Deep learning algorithms can provide automatic and reliable assessment of intracerebral hemorrhage, intraventricular hemorrhage, and perihematomal edema on CT. • Non-contrast CT-based deep learning method can be helpful to provide efficient and accurate measurements of ICH, IVH, and PHE in primary ICH patients, thereby reducing the effort and time of doctors to segment and calculate volumes of ICH, IVH, and PHE in primary ICH patients.


Asunto(s)
Edema Encefálico , Aprendizaje Profundo , Hemorragia Cerebral/diagnóstico por imagen , Edema , Humanos , Hemorragias Intracraneales , Reproducibilidad de los Resultados
18.
Phys Chem Chem Phys ; 23(46): 26428-26437, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34797354

RESUMEN

Lithium-ion batteries (LIBs) have always been the focus of researchers for energy storage applications. Here, the first-principles density functional theory method was used to explore the possibility of using stanene derived structures as LIB anodes. And such two-dimensional structures are similar to graphene or stanene, but half of the Sn atoms are replaced by group-IV atoms to form new structures, which are called Sn-X (X = C, Si, and Ge). Our calculation results showed that the optimized structure, lattice constant and other parameters are consistent with those reported in previous studies. Meanwhile, we found out that the semiconductor properties of pristine Sn-X transform into metal properties after the adsorption of Li. Then, by calculating the adsorption concentration of Li ions on the Sn-X monolayers, we found that these kinds of materials can meet the requirements of battery anodes very well, not only in terms of their open-circuit voltage, but also storage capacity. For Sn-Si and Sn-Ge, their theoretical capacities can be as high as 1095.78 mA h g-1 (Li6Sn-Si) and 840.88 mA h g-1 (Li6Sn-Ge). At last, based on the investigation of their diffusion path, Sn-X has been found to have high charge and discharge rates because of its low barrier. By reason of the foregoing, 2D Sn-X monolayers will be excellent battery anodes.

19.
Med Sci Monit ; 27: e931957, 2021 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-34552043

RESUMEN

Computer-aided diagnosis (CAD) systems have attracted extensive attention owing to their performance in the field of image diagnosis and are rapidly becoming a promising auxiliary tool in medical imaging tasks. These systems can quantitatively evaluate complex medical imaging features and achieve efficient and high-diagnostic accuracy. Deep learning is a representation learning method. As a major branch of artificial intelligence technology, it can directly process original image data by simulating the structure of the human brain neural network, thus independently completing the task of image recognition. S-Detect is a novel and interactive CAD system based on a deep learning algorithm, which has been integrated into ultrasound equipment and can help radiologists identify benign and malignant nodules, reduce physician workload, and optimize the ultrasound clinical workflow. S-Detect is becoming one of the most commonly used CAD systems for ultrasound evaluation of breast and thyroid nodules. In this review, we describe the S-Detect workflow and outline its application in breast and thyroid nodule detection. Finally, we discuss the difficulties and challenges faced by S-Detect as a precision medical tool in clinical practice and its prospects.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Neoplasias de la Tiroides/diagnóstico por imagen , Ultrasonografía/métodos , Mama/diagnóstico por imagen , Diagnóstico por Computador/métodos , Femenino , Humanos , Masculino , Sensibilidad y Especificidad , Glándula Tiroides/diagnóstico por imagen
20.
Zhongguo Zhong Yao Za Zhi ; 46(19): 5005-5014, 2021 Oct.
Artículo en Zh | MEDLINE | ID: mdl-34738395

RESUMEN

Based on the textual research on literature, the key information of Wenjing Decoction were tested and identified, and 15 batches of lyophilized powder samples of Wenjing Decoction were prepared. The specific components, including paeoniflorin, glycyrrhizin, ginsenosides(Rg_1, Re and Rb_1), glycyrrhizic acid, and paeonol, were used as indexes to establish the HPLC method for quantitative evaluation, and the content ranges and transfer rates of these components were determined. The results showed that the contents of paeoniflorin, glycyrrhizin, ginsenosides Rg_1 + Re, ginsenoside Rb_1, glycyrrhizic acid, and paeonol in the 15 batches of samples were 0.62%-0.86%, 0.25%-0.76%, 0.14%-0.30%, 0.07%-0.21%, 0.63%-1.16%, and 0.09%-0.25%, respectively, and their transfer rates from the decoction pieces to the reference materials were 14.99%-19.42%, 28.11%-40.93%, 25.92%-61.88%, 25.03%-64.06%, 23.43%-35.53%, and 5.34%-10.44%, respectively. The consistency of the transfer rates between batches indicated that the preparation process was stable. It is suggested that the contents of paeoniflorin, glycyrrhizin, ginsenosides Rg_1 + Re, ginsenoside Rb_1, glycyrrhizic acid, and paeonol in Wenjing Decoction should not be less than 0.52%, 0.35%, 0.15%, 0.10%, 0.63%, and 0.12%, respectively. In this study, we determined the contents and analyzed the quantity transfer process of the index components in Wenjing Decoction, which can provide a basis for the follow-up development of Wenjing Decoction and the quality control of related preparations.


Asunto(s)
Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Ácido Glicirrínico , Polvos , Control de Calidad
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