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Understanding the origin and early evolution of proteins is important for unveiling how the RNA world developed into an RNA-protein world. Because the composition of organic molecules in the Earth's primitive environment was plausibly not as diverse as today, the number of different amino acids used in early protein synthesis is likely to be substantially less than the current 20 proteinogenic residues. In this study, we have explored the thermal stability and RNA binding of ancestral variants of the ribosomal protein uS8 constructed from a reduced-alphabet of amino acids. First, we built a phylogenetic tree based on the amino acid sequences of uS8 from multiple extant organisms and used the tree to infer two plausible amino acid sequences corresponding to the last bacterial common ancestor of uS8. Both ancestral proteins were thermally stable and bound to an RNA fragment. By eliminating individual amino acid letters and monitoring thermal stability and RNA binding in the resulting proteins, we reduced the size of the amino acid set constituting one of the ancestral proteins, eventually finding that convergent sequences consisting of 15- or 14-amino acid alphabets still folded into stable structures that bound to the RNA fragment. Furthermore, a simplified variant reconstructed from a 13-amino-acid alphabet retained affinity for the RNA fragment, although it lost conformational stability. Collectively, RNA-binding activity may be achieved with a subset of the current 20 amino acids, raising the possibility of a simpler composition of RNA-binding proteins in the earliest stage of protein evolution.
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Aminoácidos , Proteínas Ribossômicas , Aminoácidos/genética , Aminoácidos/química , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Filogenia , Sequência de Aminoácidos , RNA , Evolução MolecularRESUMO
This paper proposes a joint estimation method for source number and DOA based on an improved convolutional neural network for unknown source number and undetermined DOA estimation. By analyzing the signal model, the paper designs a convolutional neural network model based on the existence of a mapping relationship between the covariance matrix and both the source number and DOA estimation. The model, which discards the pooling layer to avoid data loss and introduces the dropout method to improve generalization, takes the signal covariance matrix as input and the two branches of source number estimation and DOA estimation as outputs, and achieves the unfixed number of DOA estimation by filling in invalid values. Simulation experiments and analysis of the results show that the algorithm can effectively achieve the joint estimation of source number and DOA. Under the conditions of high SNR and a large snapshot number, both the proposed algorithm and the traditional algorithm have high estimation accuracy, while under the conditions of low SNR and a small snapshot, the algorithm is better than the traditional algorithm, and under the underdetermined conditions, where the traditional algorithm often fails, the algorithm can still achieve the joint estimation.
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For the multi-target DOA estimation problem of uniform linear arrays, this paper proposes a DOA estimation method based on the deep convolution neural network. The algorithm adopts the deep convolutional neural network, and the DOA estimation problem of the array signal is transformed into the inverse mapping problem of the array output covariance matrix to a binary sequence in which "1" indicates that there is a target incident in the corresponding angular direction at that position. The upper triangular array of the discrete covariance matrix is used as the data input to realize the DOA estimation of multiple sources. The simulation results show that the DOA estimation accuracy of the proposed algorithm is significantly better than that of the typical super-resolution estimation algorithm under the conditions of low SNR and small snapshot. Under the conditions of high SNR and large snapshot, the estimation accuracy of the proposed algorithm is basically the same as those of the MUSIC algorithm, ESPRIT algorithm, and ML algorithm, which are better than that of the deep fully connected neural network. The analysis of the simulation results shows that the algorithm is effective, and the time and space complexity can be further reduced by replacing the square array with the upper triangular array as the input.
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Algoritmos , Redes Neurais de Computação , Simulação por ComputadorRESUMO
To estimate the effect of bisphosphine ligands on the formation of the isomeric core structures of gold nanoclusters, the different ligation of bisphosphine ligands is usually used to participate in the construction of gold nanoclusters. Here, the selection of the different bisphosphine ligands, DPEphos and Xantphos, is performed to construct two novel gold nanoclusters, [Au11(DPEphos)4Cl2]Cl (1) and [Au11(Xantphos)4Cl2]Cl(2), which have been characterized by IR, 1H and 31P NMR, ESI-MS, XRD, SEM, XPS, TG, UV-vis, and X-ray crystal structure analysis. The structural analyses indicate that the ligation of bisphosphine ligands play a crucial role in the formation of the fascinating Au11 cores: gold nanocluster 1 includes a birdcage-shaped Au11 core with eight electrons, while gold nanocluster 2 contains a crown-shaped Au11 core with eight electrons. Meanwhile, DOS and PDOS studies indicate that the Au11 cores have a strong effect on the composition of HOMO and LUMO orbitals of gold nanoclusters. Furthermore, the different Au11 core structures lead to different optical absorption characteristics (1: 456 nm; 2: 427 nm). All these demonstrate that the ligation of bisphosphine ligands may have an important influence on constructing the stability of the isomeric core structures of gold nanoclusters.
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To understand the origin and early evolution of life it is crucial to establish characteristics of the primordial environment that facilitated the emergence and evolution of life. One important environmental factor is the pH of the primordial environment. Here, we assessed the pH-dependent thermal stabilities of previously reconstructed ancestral nucleoside diphosphate kinases and ribosomal protein uS8s. The selected proteins were likely to be present in ancient organisms such as the last common ancestor of bacteria and that of archaea. We also assessed the thermal stability of homologous proteins from extant acidophilic, neutralophilic, and alkaliphilic microorganisms as a function of pH. Our results indicate that the reconstructed ancestral proteins are more akin to those of extant alkaliphilic bacteria, which display greater stability under alkaline conditions. These findings suggest that the common ancestors of bacterial and archaeal species thrived in an alkaline environment. Moreover, we demonstrate the reconstruction method employed in this study is a valuable technique for generating alkali-tolerant proteins that can be used in a variety of biotechnological and environmental applications.
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Evolução Molecular , Proteínas , Filogenia , Proteínas/metabolismo , Bactérias/genética , Bactérias/metabolismo , Archaea/genética , Archaea/metabolismoRESUMO
Aqueous aluminum-ion batteries (AIBs) have great potential as devices for future large-scale energy storage systems due to the cost efficiency, environmentally friendly nature, and impressive theoretical energy density of Al. However, currently, available materials used as anodes for aqueous AIBs are scarce. In this study, a novel sol-gel method was used to synthesize nitrogen-doped titanium dioxide (N-TiO2) as a potential anode material for AIBs in water. The annealed N-TiO2 showed a high discharge capacity of 43.2 mAh g-1 at a current density of 3 A g-1. Analysis of the electrode kinetics revealed that the N-TiO2 anodes exhibited rapid diffusion of aluminum ions, low resistance to charge transfer, and high electronic conductivity, enabling good rate performance. The successful implementation of a nitrogen-doping strategy provides a promising approach to enhance the electrochemical characteristics of electrode materials for aqueous AIBs.
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The key to saving lives is to achieve instant and effective sealing hemostasis in the event of emergency bleeding. Herein, a plant oil-based EMTA/Zn2+ bioadhesive is prepared by a facile reaction of epoxidized soybean oil (ESO) with methacrylic acid (MAA) and tannic acid (TA), followed by the addition of zinc ions for coordination with TA. The EMTA/Zn2+ bioadhesive can be rapidly cured in situ at the wound site through photo-cross-linking under ultraviolet (UV) light-emitting diode (LED) irradiation within 30 s, achieving ultrastrong wet-tissue adhesion performance of 92.4 and 51.8 kPa to porcine skin and aortic skin after 7 days underwater, respectively. Especially, the EMTA/Zn2+ bioadhesive exhibits outstanding sealing performance in vitro with the high burst pressure of 525 mmHg (70 kPa) and 337.5 mmHg (45 kPa) to porcine skin and aortic skin, respectively. Moreover, the EMTA/Zn2+ bioadhesive not only has outstanding hemocompatibility and good biodegradability but also exhibits excellent cytocompatibility and antibacterial properties. Notably, the EMTA/Zn2+ bioadhesive has remarkable instant sealing hemostatic ability for hemorrhaging liver in vivo. Therefore, the prepared plant oil-based EMTA/Zn2+ bioadhesive can serve as a charming alternative candidate for instant sealing hemostasis in clinical applications, especially in traumatic internal organs and arterial bleeding.
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Hemostasia , Animais , Suínos , Hemostasia/efeitos dos fármacos , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Hemostáticos/química , Hemostáticos/farmacologia , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Zinco/química , Zinco/farmacologia , Camundongos , Humanos , Hemorragia/tratamento farmacológico , Pele/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Taninos/química , Taninos/farmacologia , Metacrilatos/química , Metacrilatos/farmacologiaRESUMO
Background and objectives: Patients with muscle-invasive bladder cancer (MIBC) often experience a waiting period before radical surgery for numerous reasons; however, the COVID-19 outbreak has exacerbated this problem. Therefore, it is necessary to discuss the impact of the unavoidable time of surgical delay on the outcome of patients with MIBC. Methods: In all, 165 patients from high-volume centers with pT2-pT3 MIBC, who underwent radical surgery between January 2008 and November 2020, were retrospectively evaluated. Patients' demographic and pathological information was recorded. Based on the time of surgical delay endured, patients were divided into three groups: long waiting time (> 90 days), intermediate waiting time (30-90 days), and short waiting time (≤ 30 days). Finally, each group's pathological characteristics and survival rates were compared. Results: The median time of surgical delay for all patients was 33 days (interquartile range, IQR: 16-67 days). Among the 165 patients, 32 (19.4%) were classified into the long waiting time group, 55 (33.3%) into the intermediate waiting time group, and 78 (47.3%) into the short waiting time group. The median follow-up period for all patients was 48 months (IQR: 23-84 months). The median times of surgical delay in the long, intermediate, and short waiting time groups were 188 days (IQR: 98-367 days), 39 days (IQR: 35-65 days), and 16 days (IQR: 12-22 days), respectively. The 5-year overall survival (OS) rate for all patients was 58.4%, and that in the long, intermediate, and short waiting time groups were 35.7%, 61.3%, and 64.1%, respectively (P = 0.035). The 5-year cancer-specific survival (CSS) rates in the long, intermediate, and short waiting time groups were 38.9%, 61.5%, and 65.0%, respectively (P = 0.042). The multivariate Cox regression analysis identified age, time of surgical delay, pT stage, and lymph node involvement as independent determinants of OS and CSS. Conclusion: In patients with pT2-pT3 MIBC, the time of surgical delay > 90 days can have a negative impact on survival.
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PURPOSE: This study was conducted to evaluate the correlation between the free ferrous protoporphyrin and reactive oxygen species (FH and ROS) combined test and the tumor grade and stage in a pathologically confirmed uroepithelial carcinoma (UC) patient population. PATIENTS AND METHODS: In this retrospective study, we enrolled patients newly diagnosed with UC between May 2020 and June 2021. All patients were classified as FH(+) and ROS(+), FH(+) and ROS(-), or FH(-) and ROS(-), based on the FH and ROS combined test of voided urine. Demographic information, pathological results, and status of the FH and ROS combined test were reviewed retrospectively. The relationship between FH and ROS combined test status and tumor stage and grade was evaluated using logistic regression. RESULTS: This study included 120 UC patients with a median age of 69 years (interquartile range [IQR] 62-77 years). Eighteen patients (15%) were diagnosed with upper tract urothelial carcinoma, and the others (85%) were diagnosed with bladder cancer. The pathological stages for those with FH(+) and ROS(+) at diagnosis were 25.0% Ta, 45.8% T1, and 29.2% ≥T2. The pathological stages for those with FH(+) and ROS(-) at diagnosis were 23.5% Ta, 35.3% T1, and 41.2% ≥T2. The pathological stages for those with FH(-) and ROS(-) at diagnosis were 52.6% Ta, 26.3% T1, and 21.1% ≥T2. After adjusting for clinical factors, including age, sex, and smoking history, FH(+) and ROS(-) were independent risk factors for muscle-invasive UC (≥T2 stage) at diagnosis (odds ratio [OR] 3.379; 95% confidence interval [CI] 1.103-10.355; P=0.033) in the univariate and multivariate logistic regression analyses. CONCLUSION: Among patients with newly diagnosed UC, FH(+) and ROS(-) might have an association with a more advanced pathological stage. This finding may help differentiate between patients with aggressive diseases and those who may benefit from organ-sparing surgery.
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Background: Radical nephrectomy is widely accepted as the default management option for patients with T3 renal cell carcinoma (RCC). However, it may require a certain time before surgery for various reasons. There are concerns that the delay in surgery may affect postoperative outcomes. The present study aimed to evaluate the impact of surgical wait time on survival in patients with T3 RCC. Methods: We retrospectively selected 138 patients with T3 RCC who underwent radical surgery between July 2009 and December 2019. Surgical wait time was defined as the period from initial imaging diagnosis to surgery. Patients were divided into the following 2 groups according to wait time: short-wait group(≤60 days), and long-wait group (>60 days). The clinical and pathological characteristics were evaluated. The overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) of each group were calculated and compared. Age, gender, interval, tumor size, pathological grade, Eastern Cooperative Oncology Group performance status (ECOG PS), surgical approach, year of surgery, and pathological type were included in the multivariable model. Results: This study included 91 male (65.9%) and 47 female (34.1%) patients. The median age of all patients was 60 years (interquartile range [IQR] 52-68 years). The median body mass index is 22.2â kg/m2 (IQR 18.9-24.7â kg/m2). There were 128 patients (92.8%) with pT3a disease and 10 patients (7.3%) with pT3b disease. The median surgical wait time for all patients was 16 days (IQR 10-77 days). The median surgical wait time of the short- and long-wait groups was 12 days (IQR 8-16 days) and 92 days (IQR 79-115 days), respectively. Until the last follow-up, 54 patients died. Among them, 49 patients (90.7%) died of tumor-related causes, and 5 patients (9.3%) died of other causes. There are 1 and 4 cases in the short-wait and long-wait groups, respectively. There were no significant differences in gender, ECOG PS, American society of anesthesiologists score, Charlson comorbidity index, clinical T stage, clinical N stage, and body mass index. And there were no significant differences in tumor size, surgical approach, year of surgery, pathological type, tumor grade, pathological T stage, pathological N stage, and venous involvement between the 2 groups. OS, CSS, and RFS were compared. The 5-year OS of the short- and long-wait time groups were 65.0% and 40.9%, respectively (P = .030). The 5-year CSS rates of the short- and long-wait time groups were 68.7% and 51.5%, respectively (P = .012). The 5-year RFS rates of the short- and long-wait time groups were 61.5% and 46.8%, respectively (P = .119). Multivariable analysis revealed that surgical wait time interval and tumor size were independent risk factors for OS and that wait time was also an independent risk factor for CCS. Conclusion: Delay in radical surgery beyond 60 days can negatively affect OS in patients with T3 RCC.
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Carcinoma de Células Renais/cirurgia , Neoplasias Renais/cirurgia , Tempo para o Tratamento , Idoso , Carcinoma de Células Renais/patologia , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nefrectomia , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Carga TumoralRESUMO
BACKGROUND: There is usually a surgical wait time before nephrectomy for patients with clinically localized renal cell carcinoma, and many factors can influence this preoperative wait time. A relatively prolonged wait time may cause tumor progression. Therefore, we assessed the effect of preoperative wait time on the prognosis of patients with clinically localized renal cell carcinoma. METHODS: The outcomes of 561 patients with clinically localized renal cell carcinoma who underwent nephrectomy between July 2011 and March 2017 were retrospectively evaluated. According to the wait time before surgery, we divided the patients into three groups: short-wait group (≤ 30 days), intermediate-wait group (> 30 and ≤ 90 days), and long-wait group (>90 days). The clinicopathological characteristics were evaluated, and the survival rates of the three groups were compared. RESULTS: This study included 370 male (66%) and 191(34%) female patients, with a median age of 64 years. There were 520 patients with stage T1 and 41 patients with stage T2 tumors. The median interval between diagnosis and surgery was 21 days. There were no significant differences in age, sex, Eastern Cooperative Oncology Group (ECOG) performance status, body mass index, tumor size, surgical approach, surgical procedure, pathological subtype, tumor stage, tumor grade, and residual tumor among the three groups. Overall survival(OS) and cancer-specific survival (CSS) were comparable; the 5-year OS of the short-, intermediate-, and long-wait time groups were 84.2%, 82.0%, and 89.8%, respectively (P=0.732). The 5-year CSS rates of the short-, intermediate-, and long-wait time groups were 87.1%, 88.9%, and 90.4%, respectively (P=0.896). Multivariate analysis revealed that wait time was not an independent prognostic factor for OS or CSS. CONCLUSION: Prolonged surgical wait time (> 90 days) does not influence survival in patients with clinically localized renal cell carcinoma.
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BACKGROUND AND OBJECTIVES: Due to the inevitability of waiting time for surgery, this problem seems to have become more pronounced since the outbreak of COVID-19, and due to the high incidence of preoperative hydronephrosis in upper urinary tract urothelial carcinoma (UTUC) patients, it is particularly important to explore the impact of preoperative waiting time and hydronephrosis on upper urinary urothelial carcinoma. METHODS: 316 patients with UTUC who underwent radical surgery at a high-volume center in China between January 2008 and December 2019 were included in this study. We retrospectively collected the clinicopathologic data from the medical records, including age, sex, smoking history, ECOG performance status (ECOG PS), body mass index (BMI), tumor location and size, number of lesions, T stage, N stage, surgical approach and occurrence of hydronephrosis, lymph node invasion, lymph node dissection, surgical margin, tumor necrosis, infiltrative tumor architecture, lymphovascular invasion and concomitant bladder cancer. Surgical wait time was defined as the interval between initial imaging diagnosis and radical surgery of UTUC. Hydronephrosis was defined as abnormal dilation of the renal pelvis and calyces due to obstruction of the urinary system. Firstly, all patients were divided into short-wait (<31 days), intermediate-wait (31-90 days) and long-wait (>90 days) groups according to the surgical wait time. The clinicopathological characteristics of each group were evaluated and the survival was compared. For patients with hydronephrosis, we subsequently divided them into two groups: short-wait (≤60 days) and long-wait (>60 days) groups according to the surgical wait time. Univariate and multivariate COX regression analysis were performed to evaluate the prognostic risk factor for patients with hydronephrosis. RESULTS: A total of 316 patients with UTUC were included in this study with a median surgical wait time of 22 days (IQR 11-71 days). Of the 316 patients, 173 were classified into the short-wait group (54.7%), 69 into the intermediate-wait group (21.8%) and 74 into the long-wait group (23.5%). The median follow-up time for all patients was 43 months (IQR 28-67months). The median surgical wait times of the short-wait, intermediate-wait and long-wait group were12 days (IQR 8-17days), 42days (IQR 37-65days) and 191days (IQR 129-372days), respectively. The 5-year overall survival (OS) of all patients was 54.3%. The 5-year OS of short-wait, intermediate-wait and long-wait groups were 56.4%, 59.3% and 35.1%, respectively (P=0.045). The 5-year cancer-specific survival (CSS) of short-wait, intermediate-wait and long-wait groups were 65.8%, 70.9% and 39.6%, respectively (P=0.032). In the subgroup analysis, we divided 158 UTUC patients with hydronephrosis into short-wait group (≤60 days) and long-wait group (> 60 days), 120 patients were included in the short-wait group and 38 patients in the long-wait group. The median surgical wait times of the short-wait and long-wait group were 14days (IQR 8-28days) and 174days (IQR 100-369days), respectively. The 5-year OS of long-wait group was significantly lower than the OS of short-wait group (44.2% vs. 55.1%, P =0.023). The 5-year CSS of long-wait and short-wait group were 49.1% and 61.7%, respectively (P=0.041). In multivariate Cox regression analysis of UTUC patients with hydronephrosis, surgical wait time, tumor grade, pathological T stage, and tumor size were independent risk factors for OS and CSS. Lymph node involvement was also a prognostic factor for CSS. CONCLUSION: For patients with UTUC, the surgical wait time should be limited to less than 3 months. For UTUC patients with hydronephrosis, the OS and CSS of patients with surgical wait time of more than 60 days were relatively shorted than those of patients with surgical wait time of less than 60 days.
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The complete mitochondrial DNA genome of spoon-billed sandpiper Eurynorhynchus pygmeus was determined by using the polymerase chain reaction method and the phylogenetic tree including 15 species of Charadriiformes were reconstructed to validate our samples in this study. The circular mitogenome (16,707 bp in length) contains 13 protein-coding genes, 2 rRNA genes (12S rRNA and 16S rRNA), 22 tRNA genes and a control region. The content of four kinds of bases of the complete mitochondrial DNA is 31.29% for A, 24.85% for T, 13.84% for G and 30.02% for C, respectively.
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Charadriiformes/classificação , Charadriiformes/genética , Genoma Mitocondrial , Animais , Composição de Bases , Genes Mitocondriais , Tamanho do Genoma , Fases de Leitura Aberta , Filogenia , Sequências Reguladoras de Ácido Nucleico , Análise de Sequência de DNA , Sequenciamento Completo do GenomaRESUMO
The complete mitochondrial genome of Recurvirostra avosetta (Charadriiformes: Recurvirostridea) is a circular DNA with 16,897 bp in length, which contained 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a control region. The overall base compositions of the complete mtDNA are A (31.72%), T (23.59%), G (13.56%), and C (31.13%). The non-coding regions include a control region (1333 bp) and a few intergenic spacers (range from 17 to 90). The phylogentic trees were also reconstructed to validate the samples.