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OBJECTIVE: To assess the rationality of the maximum lesion diameter of 15 mm in prostate imaging reporting and data system (PI-RADS) as a criterion for upgrading a lesion from category 4 to 5 and improve it to enhance the prediction of clinically significant prostate cancer (csPCa). METHODS: In this study, the patients who underwent prostate magnetic resonance imaging (MRI) and prostate biopsy at Peking University First Hospital from 2019 to 2022 as a development cohort, and the patients in 2023 as a validation cohort were reviewed. The localization and maximum diameter of the lesion were fully evaluated. The area under the curve (AUC) and the cut-off value of the maximum diameter of the lesion to predict the detection of csPCa were calculated from the receiver operating characteristics (ROC) curve. Confounding factors were reduced by propensity score matching (PSM). Diagnostic efficacy was compared in the validation cohort. RESULTS: Of the 589 patients in the development cohort, 358 (60.8%) lesions were located in the peripheral zone and 231 (39.2%) were located in the transition zone, and 496 (84.2%) patients detected csPCa. The median diameter of the lesions in the peripheral zone was smaller than that in the transition zone (14 mm vs. 19 mm, P < 0.001). In the ROC analysis of the maximal diameter on the csPCa prediction, there was no statistically significant difference between the peri-pheral zone (AUC=0.709) and the transition zone (AUC=0.673, P=0.585), and the cut-off values were calculated to be 11.5 mm for the peripheral zone and 16.5 mm for the migrating zone. By calcula-ting the Youden index for the cut-off values in the validation cohort, we found that the categorisation by lesion location led to better predictive results. Finally, the net reclassification index (NRI) was 0.170. CONCLUSION: 15 mm as a criterion for upgrading the PI-RADS score from 4 to 5 is reasonable but too general. The cut-off value for peripheral zone lesions is smaller than that in transitional zone. In the future consideration could be given to setting separate cut-off values for lesions in different locations.
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Imageamento por Ressonância Magnética , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética/métodos , Curva ROC , Próstata/patologia , Próstata/diagnóstico por imagem , Biópsia , Idoso , Área Sob a Curva , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
OBJECTIVE: To investigate the diagnostic efficacy of targeted biopsy combined with regional systematic biopsy in prostate cancer (PCa) in patients with prostate imaging reporting and data system v2.1 (PI-RADS v2.1) 4-5. METHODS: From January 2023 to October 2023, patients who underwent prostate biopsy for the first time with total prostate specific antigen (tPSA) ≤ 20 ng/mL and had a multi-parametric magnetic resonance imaging (mpMRI) PI-RADS of 4-5 in Peking University First Hospital were prospectively collected. All the patients underwent transrectal ultrasound-guided cognitive fusion targeted biopsy (3 cores) followed by systematic biopsy (12 cores). Various hypothetical biopsy schemes were defined based on different biopsy sites. The detection effectiveness of targeted biopsy combined with regional systematic biopsy and other biopsy schemes for prostate cancer were compared using Cochran's Q and McNemar tests. RESULTS: A total of 255 patients were enrolled, of whom 204 (80.0%) were detected with prostate adenocarcinoma and 187 (73.3%) were clinically significant with prostate cancer (csPCa). The detection rate of PCa with targeted biopsy was significantly lower than that of targeted biopsy combined with 12-core system biopsy (77.3% vs. 80.0%, P=0.016), and 71.4% (5/7) of the missed patients was csPCa. There was no significant difference in the detection rate between targeted biopsy combined with 4-core regional system biopsy and 12-core system biopsy (P>0.999), and 1 case of csPCa and clinically insignificant prostate cancer (cisPCa) were missed. There was no significant difference in the detection rate of PCa between targeted combined regional system biopsy and targeted combined lateral or traditional 6-core system biopsy and the number of cores were reduced. Missed diagnosis of targeted biopsy was correlated with the maximum diameter of the lesion (OR=0.086, 95%CI: 0.013-0.562, P=0.010). For the patients with PI-RADS 5, only 1 case of PCa was missed in 122 cases by targeted biopsy alone. For patients with PI-RADS 4, 6 PCa cases were missed among the 133 patients with targeted biopsy alone, and 1 case of csPCa and cisPCa were missed by targeted biopsy combined with regional system biopsy. The statistics of positive core counts for different biopsy schemes indicated that targeted combined regional systematic biopsy had a higher proportion of positive cores second only to targeted biopsy alone. CONCLUSION: Targeted biopsy combined with regional systematic biopsy has high diagnostic efficacy in patients with PI-RADS 4-5 and can be considered as one of the improved schemes for combined biopsy. Targeted biopsy alone is also a feasible option for patients for patients with a PI-RADS score of 5.
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Biópsia Guiada por Imagem , Próstata , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Biópsia Guiada por Imagem/métodos , Próstata/patologia , Próstata/diagnóstico por imagem , Antígeno Prostático Específico/sangue , Estudos Prospectivos , Idoso , Imageamento por Ressonância Magnética Multiparamétrica , Adenocarcinoma/patologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Ultrassonografia de Intervenção/métodosRESUMO
PURPOSE: To explore a novel biopsy scheme for prostate cancer (PCa), and test the detection rate and pathological agreement of standard systematic (SB) + targeted (TB) biopsy and novel biopsy scheme. METHODS: Positive needles were collected from 194 patients who underwent SB + TB (STB) followed by radical prostatectomy (RP). Our novel biopsy scheme, targeted and regional systematic biopsy (TrSB) was defined as TB + regional SB (4 SB-needles closest to the TB-needles). The McNemar test was utilized to compare the detection rate performance for clinical significant PCa (csPCa) and clinical insignificant PCa (ciPCa). Moreover, the accuracy, positive predictive value (PPV) and negative predictive value (NPV) were investigated. The agreement between the different biopsy schemes grade group (GG) and RP GG were assessed. The concordance between the biopsy and the RP GG was evaluated using weighted κ coefficient analyses. RESULTS: In this study, the overall detection rate for csPCa was 83.5% (162 of 194) when SB and TB were combined. TrSB showed better NPV than TB (97.0% vs. 74.4%). Comparing to STB, the TB-detection rate of csPCa had a significant difference (p < 0.01), while TrSB showed no significant difference (p > 0.999). For ciPCa, the overall detection rate was 16.5% (32 of 194). TrSB showed better PPV (96.6% vs. 83.3%) and NPV (97.6% vs. 92.9%) than TB. Comparing to STB, the detection rate of both schemes showed no significant difference (p = 0.077 and p = 0.375). All three schemes GG showed poor agreement with RP GG (TB: 43.3%, TrSB: 46.4%, STB: 45.9%). Using weighted κ, all three schemes showed no difference (TB: 0.48, TrSB: 0.51, STB: 0.51). In our subgroup analysis (PI-RADS = 4/5, n = 154), all three schemes almost showed no difference (Weighted κ: TB-0.50, TrSB-0.51, STB-0.50). CONCLUSION: Our novel biopsy scheme TrSB (TB + 4 closest SB needles) may reduce 8 cores of biopsy compared with STB (standard SB + TB), which also showed better csPCa detection rate than TB only, but the same as STB. The pathological agreement between three different biopsy schemes (TB/TrSB/STB) GG and RP GG showed no difference.
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Neoplasias da Próstata , Masculino , Humanos , Imageamento por Ressonância Magnética , Biópsia , Agulhas , ProstatectomiaRESUMO
OBJECTIVE: To evaluate objective treatment efficacy and safety, and subjective patient-reported outcomes in patients with complex ureteral strictures (US) undergoing minimally invasive lingual mucosal graft ureteroplasty (LMGU). MATERIALS AND METHODS: We prospectively enrolled patients underwent robotic or laparoscopic LMGU between May 2020 and July 2022. Clinical success was defined as symptom-free and no radiographic evidence of re-obstruction. Patient-reported outcomes, including health-related quality of life (HRQoL), mental health status and oral health-related quality of life (OHRQoL), were longitudinally evaluated before surgery, 6 and 12 months postoperatively. RESULTS: Overall, 41 consecutive patients were included. All procedures were performed successfully with 32 patients in robotic approach and 9 in laparoscopic. Forty (97.56%) patients achieved clinical success during the median follow-up of 29 (range 15-41) months. Although patients with complex US experienced poor baseline HRQoL, there was a remarkable improvement following LMGU. Specifically, the 6-month and 12-month postoperative scores were significantly improved compared to the baseline (p < 0.05) in most domains. Twenty-eight (68.3%) and 31 (75.6%) patients had anxiety and depression symptoms before surgery, respectively. However, no significant decrease in the incidence of these symptoms was observed postoperatively. Moreover, there was no significant deterioration of OHRQoL at 6 months and 12 months postoperatively when compared to the baseline. CONCLUSIONS: LMGU is a safe and efficient procedure for complex ureteral reconstruction that significantly improves patient-reported HRQoL without compromising OHRQoL. Assessing patients' quality of life enables us to monitor postoperative recovery and progress, which should be considered as one of the criteria for surgical success.
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Procedimentos Cirúrgicos Robóticos , Ureter , Obstrução Ureteral , Humanos , Constrição Patológica/cirurgia , Qualidade de Vida , Ureter/cirurgia , Obstrução Ureteral/cirurgia , Resultado do Tratamento , Procedimentos Cirúrgicos Robóticos/métodos , Estudos RetrospectivosRESUMO
The development of green, renewable energy conversion and storage systems is an urgent task to address the energy crisis and environmental issues in the future. To achieve high performance, stable, and safe operation of energy conversion and storage systems, energy materials need to be modified and fabricated through rationalization. Among various modification and fabrication strategies, ion beam technology has been widely used to introduce various defects/dopants into energy materials and fabricate various nanostructures, where the structure, composition, and property of prefabricated materials can be further accurately tailored to achieve better performance. In this paper, we review the recent progress in the application of ion beam technology in material modification and fabrication, focusing on nanostructured energy materials for energy conversion and storage including photo- (electro-) water splitting, batteries (solar cells, fuel cells, and metal-ion batteries), supercapacitors, thermoelectrics, and hydrogen storage. This review first provides a brief basic overview of ion beam technology and describes the classification and technological advantages of ion beam technology in the modification and fabrication of materials. Then, modification of energy materials by ion beams is reviewed mainly concerning doping and defect introduction. Fabrication of energy materials is also discussed mainly in terms of heterojunctions, nanoparticles, nanocavities, and other nanostructures. In particular, we emphasize the advantages of ion beam technology in improving the performance of energy materials. Finally, we point out our understanding of challenges and future perspectives in applying ion beam technology for the modification and fabrication of energy materials.
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ABSTRACT Objective: To evaluate objective treatment efficacy and safety, and subjective patient-reported outcomes in patients with complex ureteral strictures (US) undergoing minimally invasive lingual mucosal graft ureteroplasty (LMGU). Materials and Methods: We prospectively enrolled patients underwent robotic or laparoscopic LMGU between May 2020 and July 2022. Clinical success was defined as symptom-free and no radiographic evidence of re-obstruction. Patient-reported outcomes, including health-related quality of life (HRQoL), mental health status and oral health-related quality of life (OHRQoL), were longitudinally evaluated before surgery, 6 and 12 months postoperatively. Results: Overall, 41 consecutive patients were included. All procedures were performed successfully with 32 patients in robotic approach and 9 in laparoscopic. Forty (97.56%) patients achieved clinical success during the median follow-up of 29 (range 15-41) months. Although patients with complex US experienced poor baseline HRQoL, there was a remarkable improvement following LMGU. Specifically, the 6-month and 12-month postoperative scores were significantly improved compared to the baseline (p < 0.05) in most domains. Twenty-eight (68.3%) and 31 (75.6%) patients had anxiety and depression symptoms before surgery, respectively. However, no significant decrease in the incidence of these symptoms was observed postoperatively. Moreover, there was no significant deterioration of OHRQoL at 6 months and 12 months postoperatively when compared to the baseline. Conclusions: LMGU is a safe and efficient procedure for complex ureteral reconstruction that significantly improves patient-reported HRQoL without compromising OHRQoL. Assessing patients' quality of life enables us to monitor postoperative recovery and progress, which should be considered as one of the criteria for surgical success.
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PURPOSE: To evaluate the detection rates of prostate cancer (PCa) and clinically significant prostate cancer (CSPCa) detection via target biopsy (TB), systematic biopsy (SB), and combined biopsy (CB) in patients with PI-RADS 5 lesions. METHODS: Patients with at least one PI-RADS 5 lesion were retrospectively enrolled in a prospectively collected database. The patients underwent multiparametric magnetic resonance imaging (mpMRI) followed by transrectal TB of PI-RADS 5 lesions and SB. The PCa and CSPCa detection rates and cores of TB and SB were compared with those of CB. RESULTS: In 585 patients, prostate biopsy revealed PCa in 560 cases (95.73%) and CSPCa in 549 cases (93.85%). PCa was detected in T2 patients (93.13%, 217/233) and in T3/4 patients (97.44%, 343/352). CSPCa was detected in T2 patients (89.27%, 208/233) and in T3/4 patients (96.87%, 341/352). The positive rates of TB for T2/3/4, T3/4, and T2 were 94.02%, 96.21%, and 90.56%, respectively. SB added 1.71% (10/585) PCa and 1.37% (8/585) CSPCa detection to TB. There was no difference between TB and SB in detecting different stages of cancer (p > 0.05). In the biopsy core analysis, TB had fewer biopsy cores and a higher detection rate than SB (all p < 0.05). CONCLUSIONS: In patients with PI-RADS score 5 lesions, TB can achieve the same detection rate as, with fewer biopsy cores than, CB. SB adds minimal clinical value and can be omitted for these patients.
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We demonstrate ultra-broadband spectral combining of ultrashort pulses from Yb-doped fiber amplifiers, with coherently spectrally synthesized pulse shaping, to achieve tens-of-fs pulses. This method can fully compensate for gain narrowing and high order dispersion over broad bandwidth. We produce 42fs pulses by spectrally synthesizing three chirped-pulse fiber amplifiers and two programmable pulse shapers across an 80nm overall bandwidth. To the best of our knowledge, this is the shortest pulse duration achieved from a spectrally combined fiber system at one-micron wavelength. This work provides a path toward high-energy, tens-of-fs fiber chirped-pulse amplification systems.
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NiFe layered double hydroxide (NiFe LDH) is a promising material with multiple functions. In this communication, a novel method is used to prepare NiFe LDH. This synthesis method is achieved via galvanic-cell corrosion between nickel and iron substrates in aqueous solutions containing a halogen group anion (e.g., Cl) at ambient temperature. The as-prepared NiFe LDH electrodes are developed as electrocatalysts for the oxygen evolution reaction (OER) and exhibit excellent catalytic activities and durability. This work provides an energy-efficient, cost-effective, and scaled-up corrosion engineering approach for manufacturing NiFe LDH materials.
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Purpose: To develop a cascaded deep learning model trained with apparent diffusion coefficient (ADC) and T2-weighted imaging (T2WI) for fully automated detection and localization of clinically significant prostate cancer (csPCa). Methods: This retrospective study included 347 consecutive patients (235 csPCa, 112 non-csPCa) with high-quality prostate MRI data, which were randomly selected for training, validation, and testing. The ground truth was obtained using manual csPCa lesion segmentation, according to pathological results. The proposed cascaded model based on Res-UNet takes prostate MR images (T2WI+ADC or only ADC) as inputs and automatically segments the whole prostate gland, the anatomic zones, and the csPCa region step by step. The performance of the models was evaluated and compared with PI-RADS (version 2.1) assessment using sensitivity, specificity, accuracy, and Dice similarity coefficient (DSC) in the held-out test set. Results: In the test set, the per-lesion sensitivity of the biparametric (ADC + T2WI) model, ADC model, and PI-RADS assessment were 95.5% (84/88), 94.3% (83/88), and 94.3% (83/88) respectively (all p > 0.05). Additionally, the mean DSC based on the csPCa lesions were 0.64 ± 0.24 and 0.66 ± 0.23 for the biparametric model and ADC model, respectively. The sensitivity, specificity, and accuracy of the biparametric model were 95.6% (108/113), 91.5% (665/727), and 92.0% (773/840) based on sextant, and were 98.6% (68/69), 64.8% (46/71), and 81.4% (114/140) based on patients. The biparametric model had a similar performance to PI-RADS assessment (p > 0.05) and had higher specificity than the ADC model (86.8% [631/727], p< 0.001) based on sextant. Conclusion: The cascaded deep learning model trained with ADC and T2WI achieves good performance for automated csPCa detection and localization.
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INTRODUCTION: Prostatic stromal tumours of uncertain malignant potential (STUMPs) are rare prostate tumours. The purpose of this study was to investigate the magnetic resonance imaging features of STUMPs. METHODS: A total of 12 patients with STUMP confirmed with pathology who underwent MRI from 2012 to 2020 were retrospectively reviewed. Pathological characteristics including histopathology and immunohistochemistry were also recorded. RESULTS: Among 12 STUMPs, the tumours were detected in the peripheral zone (41.7%[n = 5]) and transitional zone (58.3% [n = 7]) of the prostate. 8 cases (66.7%) were round shape. All lesions were well-defined and compressed the adjacent structures but without signs of an invasion. Homogeneous T1WI and heterogeneous T2WI signals were observed in the STUMPs. The tumours were mainly composed of solid components, while intratumoral cystic change (58.3%[n = 7]) and haemorrhage (8.3%[n = 1]) were seen. 10 cases(83.3%) were seen as relatively high DWI signal, while 2 cases(16.7%) with no increase in DWI. The mean ADC value was 1.084 ± 0.193 (range: 0.864-1.489 × 10-3 mm2 /s). STUMPs had heterogeneous enhancement, with persistent or gradual enhancement. In immunohistochemical staining, Vim, CD34, PR and SMA were positive in the majority of STUMPs. CONCLUSION: MRI features of STUMP are presented as regular, well-defined and isolated prostatic mass with intact pseudocapsule. The presence of heterogeneous T2WI signal, intratumoral cystic change, slightly low mean ADC value and persistent or gradual enhancement may help predict the STUMPs.
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Neoplasias da Próstata , Neoplasias de Tecidos Moles , Masculino , Humanos , Próstata/diagnóstico por imagem , Próstata/patologia , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Imagem de Difusão por Ressonância Magnética/métodosRESUMO
An 8-beam, diffractive coherent beam combiner is phase controlled by a learning algorithm trained while optical phases drift, using a differential mapping technique. Combined output power is stable to 0.4% with 95% of theoretical maximum efficiency, limited by the diffractive element.
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3,3-Disubstituted oxetanes have been utilized as bioisosteres for gem-dimethyl and cyclobutane functionalities. We report the discovery of a novel class of oxetane indole-amine 2,3-dioxygenase (IDO1) inhibitors suitable for Q3W (once every 3 weeks) oral and parenteral dosing. A diamide class of IDO inhibitors was discovered through an automated ligand identification system (ALIS). Installation of an oxetane and fluorophenyl dramatically improved the potency. Identification of a biaryl moiety as an unconventional amide isostere addressed the metabolic liability of amide hydrolysis. Metabolism identification (Met-ID)-guided target design and the introduction of polarity resulted in the discovery of potent IDO inhibitors with excellent pharmacokinetic (PK) profiles in multiple species. To enable rapid synthesis of the key oxetane intermediate, a novel oxetane ring cyclization was also developed, as well as optimization of a literature route on kg scale. These IDO inhibitors may enable unambiguous proof-of-concept testing for the IDO1 inhibition mechanism for oncology.
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Inibidores Enzimáticos , Éteres Cíclicos , Amidas , Ciclização , Inibidores Enzimáticos/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismoRESUMO
Comprehensive synthetic strategies afforded a diverse set of structurally unique bicyclic proline-containing arginase inhibitors with a high degree of three-dimensionality. The analogs that favored the Cγ-exo conformation of the proline improved the arginase potency over the initial lead. The novel synthetic strategies reported here not only enable access to previously unknown stereochemically complex proline derivatives but also provide a foundation for the future synthesis of bicyclic proline analogs, which incorporate inherent three-dimensional character into building blocks, medicine, and catalysts and could have a profound impact on the conformation of proline-containing peptides and macrocycles.
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Recent data suggest that the inhibition of arginase (ARG) has therapeutic potential for the treatment of a number of indications ranging from pulmonary and vascular disease to cancer. Thus, high demand exists for selective small molecule ARG inhibitors with favorable druglike properties and good oral bioavailability. In light of the significant challenges associated with the unique physicochemical properties of previously disclosed ARG inhibitors, we use structure-based drug design combined with a focused optimization strategy to discover a class of boronic acids featuring a privileged proline scaffold with superior potency and oral bioavailability. These compounds, exemplified by inhibitors 4a, 18, and 27, demonstrated a favorable overall profile, and 4a was well tolerated following multiple days of dosing at concentrations that exceed those required for serum arginase inhibition and concomitant arginine elevation in a syngeneic mouse carcinoma model.
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Herein the discovery of potent IDO1 inhibitors with low predicted human dose is discussed. Metabolite identification (MetID) and structural data were used to strategically incorporate cyclopropane rings into this tetrahydronaphthyridine series of IDO1 inhibitors to improve their metabolic stability and potency. Enabling synthetic chemistry was developed to construct these unique fused cyclopropyl compounds, leading to inhibitors with improved pharmacokinetics and human whole blood potency and a predicted human oral dose as low as 9 mg once daily (QD).
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A series of IDO1 inhibitors containing a decahydroquinoline, decahydro-1,6-naphthyridine, or octahydro-1H-pyrrolo[3,2-c]pyridine scaffold were identified with good cellular and human whole blood activity against IDO1. These inhibitors contain multiple chiral centers and all diastereomers were separated. The absolute stereochemistry of each isomers were not determined. Compounds 15 and 27 stood out as leads due to their good cellular as well as human whole blood IDO1 inhibition activity, low unbound clearance, and reasonable mean residence time in rat cassette PK studies.
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Inibidores Enzimáticos/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Naftiridinas/farmacologia , Pirróis/farmacologia , Quinolinas/farmacologia , Animais , Domínio Catalítico , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacocinética , Células HeLa , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/química , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Simulação de Acoplamento Molecular , Naftiridinas/síntese química , Naftiridinas/metabolismo , Naftiridinas/farmacocinética , Pirróis/síntese química , Pirróis/metabolismo , Pirróis/farmacocinética , Quinolinas/síntese química , Quinolinas/metabolismo , Quinolinas/farmacocinética , Ratos , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
A novel series of IDO1 inhibitors have been identified with good IDO1 Hela cell and human whole blood activity. These inhibitors contain an indoline or a 3-azaindoline scaffold. Their structure-activity-relationship studies have been explored. Compounds 37 and 41 stood out as leads due to their good potency in IDO1 Hela assay, good IDO1 unbound hWB IC50s, reasonable unbound clearance, and good MRT in rat and dog PK studies.
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Compostos Aza/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indóis/farmacologia , Animais , Compostos Aza/síntese química , Compostos Aza/química , Cães , Relação Dose-Resposta a Droga , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Indóis/síntese química , Indóis/química , Masculino , Estrutura Molecular , Ratos , Ratos Wistar , Relação Estrutura-AtividadeRESUMO
We have generated 81 independently controllable beams using a spatial light modulator and combined them on a diffractive combiner, to characterize the combiner and develop a fast phase error detection scheme. A key parameter of the diffractive combiner is measured in a new way, enabling an efficient combination when programming calibrated phases of each beam. This testbed provides a platform for development of advanced feedback phase control of high channel-count beam combination.
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We develop a rapidly converging algorithm for stabilizing a large channel-count diffractive optical coherent beam combination. An 81-beam combiner is controlled by a novel, machine-learning based, iterative method to correct the optical phases, operating on an experimentally calibrated numerical model. A neural-network is trained to detect phase errors based on interference pattern recognition of uncombined beams adjacent to the combined one. Due to the non-uniqueness of solutions in the full space of possible phases, the network is trained within a limited phase perturbation/error range. This also reduces the number of samples needed for training. Simulations have proven that the network can converge in one step for small phase perturbations. When the trained neural-network is applied to a realistic case of 360 degree full range, an iterative scheme exploits random walking at the beginning, with the accuracy of prediction on phase feedback direction, to allow the neural-network to step into the training range for fast convergence. This neural-network-based iterative method of phase detection works tens of times faster than the commonly used stochastic parallel gradient descent approach (SPGD) using a single-detector and random dither when both are tested with random phase perturbations.