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1.
Cell ; 185(9): 1506-1520.e17, 2022 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-35385687

RESUMEN

Schistosomes cause morbidity and death throughout the developing world due to the massive numbers of eggs female worms deposit into the blood of their host. Studies dating back to the 1920s show that female schistosomes rely on constant physical contact with a male worm both to become and remain sexually mature; however, the molecular details governing this process remain elusive. Here, we uncover a nonribosomal peptide synthetase that is induced in male worms upon pairing with a female and find that it is essential for the ability of male worms to stimulate female development. We demonstrate that this enzyme generates ß-alanyl-tryptamine that is released by paired male worms. Furthermore, synthetic ß-alanyl-tryptamine can replace male worms to stimulate female sexual development and egg laying. These data reveal that peptide-based pheromone signaling controls female schistosome sexual maturation, suggesting avenues for therapeutic intervention and uncovering a role for nonribosomal peptides as metazoan signaling molecules.


Asunto(s)
Péptidos , Feromonas , Schistosoma/crecimiento & desarrollo , Animales , Femenino , Masculino , Biosíntesis de Péptidos Independientes de Ácidos Nucleicos , Triptaminas
2.
PLoS Pathog ; 20(1): e1011949, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38285715

RESUMEN

Schistosomes are flatworm parasites that undergo a complex life cycle involving two hosts. The regulation of the parasite's developmental processes relies on both coding RNAs and non-coding RNAs. However, the roles of non-coding RNAs, including long non-coding RNAs (lncRNAs) in schistosomes remain largely unexplored. Here we conduct advanced RNA sequencing on male and female S. japonicum during their pairing and reproductive development, resulting in the identification of nearly 8,000 lncRNAs. This extensive dataset enables us to construct a comprehensive co-expression network of lncRNAs and mRNAs, shedding light on their interactions during the crucial reproductive stages within the mammalian host. Importantly, we have also revealed a specific lncRNA, LNC3385, which appears to play a critical role in the survival and reproduction of the parasite. These findings not only enhance our understanding of the dynamic nature of lncRNAs during the reproductive phase of schistosomes but also highlight LNC3385 as a potential therapeutic target for combating schistosomiasis.


Asunto(s)
Parásitos , ARN Largo no Codificante , Schistosoma japonicum , Esquistosomiasis , Animales , Masculino , Femenino , Schistosoma japonicum/genética , ARN Largo no Codificante/genética , ARN sin Sentido/genética , Esquistosomiasis/parasitología , Parásitos/genética , Mamíferos
3.
J Immunol ; 212(4): 607-616, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38169327

RESUMEN

Helminth infections are common in animals. However, the impact of a helminth infection on the function of hematopoietic stem cells (HSCs) and other hematopoietic cells has not been comprehensively defined. In this article, we describe the hematopoietic response to infection of mice with Schistosoma mansoni, a parasitic flatworm that causes schistosomiasis. We analyzed the frequency or number of hematopoietic cell types in the bone marrow, spleen, liver, thymus, and blood and observed multiple hematopoietic changes caused by infection. Schistosome infection impaired bone marrow HSC function after serial transplantation. Functional HSCs were present in the infected liver. Infection blocked bone marrow erythropoiesis and augmented spleen erythropoiesis, observations consistent with the anemia and splenomegaly prevalent in schistosomiasis patients. This work defines the hematopoietic response to schistosomiasis, a debilitating disease afflicting more than 200 million people, and identifies impairments in HSC function and erythropoiesis.


Asunto(s)
Médula Ósea , Esquistosomiasis , Humanos , Ratones , Animales , Células Madre Hematopoyéticas/metabolismo , Hematopoyesis/fisiología , Eritropoyesis , Bazo , Esquistosomiasis/complicaciones
4.
Langmuir ; 40(24): 12744-12754, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38838080

RESUMEN

Appropriate capillary effects are beneficial for controlling the wet powder performance and agglomerate formation. As water content rises, the funicular regime supplants the pendular regime as the predominant state in wet granular media. The displacement of grains leading to the stretching of funicular liquid bridges until rupture is an interesting and common phenomenon. Utilizing Surface Evolver software (an energy minimization approach), this work develops an efficient and accurate numerical model to describe liquid interactions among three spherical grains. The effects of liquid volume, contact angle, grain size ratio, grain-pair gap, and separation distance on the capillary forces and rupture distances are investigated. Notably, we present a modified closed-form equation for predicting the rupture distance of funicular bridges between three grains, which reflects the coupled effects of the contact angle, grain size, and liquid volume on rupture distance. This present study provides insights for incorporating capillary effects into mechanical models relying on microassembly composed of several grains in bidisperse particulate systems. Additionally, the numerical findings confirm some findings regarding the splitting of funicular bridges.

5.
Phys Chem Chem Phys ; 26(22): 15804-15817, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38775810

RESUMEN

Volatile organic compounds (VOCs) are common contaminants found as indoor as well as outdoor pollutants, which can induce acute or chronic health hazards to the human physiological system. The catalytic oxidation method is widely considered as one of the effective methods for removing VOCs, and the development of highly effective catalysts is highly urgent for booming this interesting field. This review focuses on the recent progress of VOC oxidation catalyzed by supported nano-sized precious metal catalysts, and discusses the effects of metal composition, supports, size, and morphology on the catalytic activity. In addition, the roles played by both nano-sized precious metals and supports in enhancing the performance of catalytic VOCs are also systematically discussed, which will guide the further development of more advanced VOC catalysts.

6.
Environ Geochem Health ; 46(9): 328, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39012544

RESUMEN

Alpine ecosystems are important terrestrial carbon (C) pools, and microbial decomposers play a key role in litter decomposition. Microbial metabolic limitations in these ecosystems, however, remain unclear. The objectives of this study aim to elucidate the characteristics of microbial nutrient limitation and their C use efficiency (CUE), and to evaluate their response to environmental factors. Five ecological indicators were utilized to assess and compare the degree of microbial elemental homeostasis and the nutrient limitations of the microbial communities among varying stages of litter decomposition (L, F, and H horizon) along an altitudinal gradient (2800, 3000, 3250, and 3500 m) under uniform vegetation (Abies fabri) on Gongga Mountain, eastern Tibetan Plateau. In this study, microorganisms in the litter reached a strictly homeostatic of C content exclusively during the middle stage of litter decomposition (F horizon). Based on the stoichiometry of soil enzymes, we observed that microbial N- and P-limitation increased during litter degradation, but that P-limitation was stronger than N-limitation at the late stages of degradation (H horizon). Furthermore, an increase in microbial CUE corresponded with a reduction in microbial C-limitation. Additionally, redundancy analysis (RDA) based on forward selection further showed that microbial biomass C (MBC) is closely associated with the enzyme activities and their ratios, and MBC was also an important factor in characterizing changes in microbial nutrient limitation and CUE. Our findings suggest that variations in MBC, rather than N- and P-related components, predominantly influence microbial metabolic processes during litter decomposition on Gongga Mountain, eastern Tibetan Plateau.


Asunto(s)
Carbono , Microbiología del Suelo , Carbono/metabolismo , Nitrógeno/metabolismo , Tibet , Fósforo/metabolismo , Nutrientes/metabolismo , Hojas de la Planta/metabolismo , Suelo/química , Biomasa , Ecosistema , Bacterias/metabolismo
7.
Zhongguo Zhong Yao Za Zhi ; 49(11): 2930-2939, 2024 Jun.
Artículo en Zh | MEDLINE | ID: mdl-39041152

RESUMEN

To investigate the effects of different initial processing methods on the quality of Fritillaria taipaiensis, this study explored the effects of anti-browning treatment, drying methods, and drying temperatures on the commercial characters, chromaticity values, and alkaloid and nucleoside components of Fritillariae Taipaiensis Bulbus. The results were comprehensively evaluated through correlation analysis(CA), principal component analysis(PCA), and hierarchical clustering analysis(HCA). Compared with those of the direct drying group(WD60), the chromaticity values(ΔE*) of the groups with scraped outer skin( FHB1) and mixed lime powder treatments(FHB2) were significantly reduced, indicating the inhibition of the browning process. The total alkaloid content of the group with mixed raw soil treatment(FHB3) and the FHB2 group showed no significant change, whereas that of the group with 5%Na Cl O solution rinse treatment(FHB4) was the lowest. Compared with air-blast dried(WD50) samples, the ΔE* values of freezedried(FS6) and vacuum-dried(FS5) samples were significantly decreased, with an increase in total alkaloid contents. Conversely,the ΔE* values of shade-dried(FS1) and sun-dried(FS2) samples were significantly increased, with severe browning and low total alkaloid contents. The total alkaloid contents of heat-pump-dried(FS4) samples showed no significant change, and their ΔE* value was significantly decreased, with a light degree of browning and favorable commercial characters. The total alkaloid content of air-blast dried samples initially increased and then decreased within the range of 40-80 ℃, and the highest content was recorded at 70 ℃. The ΔE* values of high-temperature air-blast dried samples(70-80 ℃) were smaller with a light degree of browning, whereas their texture was compact and lacked powder. CA revealed a significant relationship between the uracil content and chromaticity value of the samples(P< 0. 05). The clustering relationships among samples subjected to different treatments were visualized via PCA and HCA. The results showed that FHB2 and air-blast drying(50-60 ℃) were more suitable for large-scale production, and heat pump drying could be a promising direction for future development. This study provides a scientific basis for optimizing the initial processing methods of Fritillaria taipaiensis.


Asunto(s)
Alcaloides , Medicamentos Herbarios Chinos , Fritillaria , Fritillaria/química , Alcaloides/análisis , Alcaloides/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Análisis de Componente Principal , Desecación/métodos
8.
New Phytol ; 239(5): 1651-1664, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37322611

RESUMEN

The continuous imbalance between nitrogen (N) and phosphorus (P) deposition is expected to shift many ecosystems from N- to P limitation. Extraradical hyphae of ectomycorrhizal (ECM) fungi play important roles in plant nutrient acquisition under nutrient deficiency. However, whether and how ECM hyphae enhance soil P availability to alleviate N-induced P deficiency remains unclear. We investigated the impacts of ECM hyphae on transformations among different soil P fractions and underlying mechanisms under N deposition in two ECM-dominated forests. Ectomycorrhizal hyphae enhanced soil P availability under N addition by stimulating mineralization of organic P (Po) and desorption and solubilization of secondary mineral P, as indicated by N-induced increase in positive hyphal effect on plant-available P pool and negative hyphal effects on Po and secondary mineral P pools. Moreover, ECM hyphae increased soil phosphatase activity and abundance of microbial genes associated with Po mineralization and inorganic P solubilization, while decreasing concentrations of Fe/Al oxides. Our results suggest that ECM hyphae can alleviate N-induced P deficiency in ECM-dominated forests by regulating interactions between microbial and abiotic factors involved in soil P transformations. This advances our understanding of plant acclimation strategies via mediating plant-mycorrhiza interactions to sustain forest production and functional stability under changing environments.


Asunto(s)
Micorrizas , Fósforo , Ecosistema , Hifa , Nitrógeno , Bosques , Micorrizas/fisiología , Minerales , Plantas , Suelo , Microbiología del Suelo
9.
Microb Pathog ; 184: 106335, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37673353

RESUMEN

BACKGROUND: Increasing studies have shown that the imbalance of the respiratory microbial flora is related to the occurrence of COPD, the severity and frequency of exacerbations and mortality.However, it remains unclear how the sputum microbial flora differs during exacerbations in COPD patients manifesting emphysema phenotype, chronic bronchitis with emphysema phenotype and asthma-COPD overlap phenotype. METHODS: Sputum samples were obtained from 29 COPD patients experiencing acute exacerbations who had not received antibiotics or systemic corticosteroids within the past four weeks.Patients were divided into three groups;emphysema phenotype(E);chronic bronchitis with emphysema phenotype(B+E) and asthma-COPD overlap phenotype(ACO).We utilized metagenomic Next Generation Sequencing (mNGS) technology to analyze the sputum microbial flora in COPD patients with different phenotypes during exacerbations. RESULTS: There was no significant difference in alpha diversity and beta diversity among three groups.The microbial flora composition was similar in all three groups during exacerbations except for a significant increase in Streptococcus mitis in ACO.Through network analysis,we found Candidatus Saccharibacteria oral taxon TM7x and Fusobacterium necrophorum were the core nodes of the co-occurrence network in ACO and E respectively.They were positively correlated with some species and play a synergistic role.In B+E,Haemophilus pittmaniae and Klebsiella pneumoniae had a synergistic effect.Besides,some species among the three groups play a synergistic or antagonistic role.Through Spearman analysis,we found the relative abundance of Streptococcus mitis was negatively correlated with the number of hospitalizations in the past year(r = -0.410,P = 0.027).We also observed that the relative abundance of Prevotella and Prevotella melaninogenica was negatively correlated with age(r = -0.534,P = 0.003;r = -0.567,P = 0.001),while the relative abundance of Streptococcus oralis and Actinomyces odontolyticus was positively correlated with age(r = 0.570,P = 0.001;r = 0.480,P = 0.008).In addition,the relative abundance of Prevotella melaninogenica was negatively correlated with peripheral blood neutrophil ratio and neutrophil to lymphocyte ratio(r = -0.479,P = 0.009;r = -0.555,P = 0.002),while the relative abundance of Streptococcus sanguinis was positively correlated with peripheral blood neutrophil ratio and neutrophil to lymphocyte ratio (r = 0.450,P = 0.014;r = 0.501,P = 0.006).There was also a significant positive correlation between Oribacterium and blood eosinophil counts(r = 0.491,P = 0.007). CONCLUSION: Overall,we analyzed the sputum microbiota of COPD patients with different phenotypes and its relationship with clinical indicators, and explored the relationships between microbiota and inflammation in COPD.We hope to alter the prognosis of patients by inhibiting specific bacterial taxa related to inflammation and using guide individualized treatment in the future research.


Asunto(s)
Asma , Bronquitis Crónica , Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Esputo , Fenotipo , Inflamación
10.
PLoS Biol ; 17(5): e3000254, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31067225

RESUMEN

Schistosomes infect over 200 million people. The prodigious egg output of these parasites is the sole driver of pathology due to infection, yet our understanding of sexual reproduction by schistosomes is limited because normal egg production is not sustained for more than a few days in vitro. Here, we describe culture conditions that support schistosome sexual development and sustained egg production in vitro. Female schistosomes rely on continuous pairing with male worms to fuel the maturation of their reproductive organs. Exploiting these new culture conditions, we explore the process of male-stimulated female maturation and demonstrate that physical contact with a male worm, and not insemination, is sufficient to induce female development and the production of viable parthenogenetic haploid embryos. We further report the characterization of a nuclear receptor (NR), which we call Vitellogenic Factor 1 (VF1), that is essential for female sexual development following pairing with a male worm. Taken together, these results provide a platform to study the fascinating sexual biology of these parasites on a molecular level, illuminating new strategies to control schistosome egg production.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Parásitos/crecimiento & desarrollo , Schistosoma mansoni/crecimiento & desarrollo , Animales , Ácido Ascórbico/farmacología , Colesterol/farmacología , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/metabolismo , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Femenino , Haploidia , Humanos , Masculino , Ratones , Óvulo/efectos de los fármacos , Óvulo/fisiología , Partenogénesis/efectos de los fármacos , Receptores Citoplasmáticos y Nucleares/metabolismo , Reproducción/efectos de los fármacos , Schistosoma mansoni/efectos de los fármacos , Maduración Sexual/efectos de los fármacos
11.
Int J Urol ; 29(10): 1188-1194, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35764596

RESUMEN

OBJECTIVE: To determine whether robot-assisted laparoscopic partial nephrectomy (RALPN) can benefit patients in terms of functional recovery in the treatment of renal hilar tumors compared to conventional laparoscopic partial nephrectomy (CLPN). METHODS: Between January 2019 and July 2021, patients with hilar tumors who underwent partial nephrectomy (PN) were acquired at our center and were classified into RALPN and CLPN groups. Ipsilateral parenchymal volume (IPV) and glomerular filtration rate (GFR) were determined independently 3-5 days before and 3 months after PN using contrast-enhanced computed tomography and nuclear renal scans. Pearson correlation was used to determine the link between ipsilateral GFR preservation and IPV preserved. Concurrently, multivariable analysis was employed to determine characteristics associated with functional recovery. RESULTS: A total of 96 patients with hilar tumors were studied, of which 41 received RALPN and 55 received CLPN. Excisional parenchymal volume was 27 and 37 cm3 (p = 0.005) in RALPN and CLPN groups, respectively, and IPV preserved was 77% and 68% (p < 0.001). Furthermore, the ipsilateral GFR preserved was 77.7% and 75.3%, respectively (p = 0.003). On Pearson correlation, ipsilateral GFR preservation was linked with IPV preserved (r = 0.36, p < 0.001). According to a multivariate study, baseline GFR, IPV preserved, and surgical procedures (RALPN vs. CLPN) were significant factors influencing functional recovery. CONCLUSION: Our study suggests that RALPN, rather than CLPN, can achieve better functional recovery in the treatment of hilar tumors due to its ability to win more IPV preserved. RALPN should be recommended as the first-line treatment for hilar tumors, but randomized controlled trials are required to validate our findings.


Asunto(s)
Neoplasias Renales , Laparoscopía , Robótica , Tasa de Filtración Glomerular , Humanos , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Laparoscopía/métodos , Nefrectomía/métodos , Estudios Retrospectivos , Resultado del Tratamiento
12.
Biodegradation ; 32(3): 229-249, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33825095

RESUMEN

To further reduce the energy consumption in the wastewater biological nitrogen removal process, partial nitrification and its integrated processes have attracted increasing attentions owing to their economy and efficiency. Shortening the steps of ammonia oxidation to nitrate saves a large amount of aeration, and the accumulated nitrite could be reduced by denitritation or anammox, which requires less electron donors compared with denitrification. Therefore, the strategies through mainstream suppression and sidestream inhibition for the achievement of partial nitrification in recent years are reviewed. Specifically, the enrichment strategies of functional microorganisms are obtained on the basis of their growth and metabolic characteristics under different selective pressures. Furthermore, the promising developments, current application bottlenecks and possible future trends of some biological nitrogen removal processes integrating partial nitrification are discussed. The obtained knowledge would provide a new idea for the fast realization of economic, efficient and long-term stable partial nitrification and biological nitrogen removal process.


Asunto(s)
Nitrificación , Nitrógeno , Biodegradación Ambiental , Reactores Biológicos , Desnitrificación , Oxidación-Reducción , Aguas Residuales
13.
Sensors (Basel) ; 21(20)2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34695949

RESUMEN

The novel sensing technology airborne passive bistatic radar (PBR) has the problem of being affecting by multipath components in the reference signal. Due to the movement of the receiving platform, different multipath components contain different Doppler frequencies. When the contaminated reference signal is used for space-time adaptive processing (STAP), the power spectrum of the spatial-temporal clutter is broadened. This can cause a series of problems, such as affecting the performance of clutter estimation and suppression, increasing the blind area of target detection, and causing the phenomenon of target self-cancellation. To solve this problem, the authors of this paper propose a novel algorithm based on sparse Bayesian learning (SBL) for direct clutter estimation and multipath clutter suppression. The specific process is as follows. Firstly, the space-time clutter is expressed in the form of covariance matrix vectors. Secondly, the multipath cost is decorrelated in the covariance matrix vectors. Thirdly, the modeling error is reduced by alternating iteration, resulting in a space-time clutter covariance matrix without multipath components. Simulation results showed that this method can effectively estimate and suppress clutter when the reference signal is contaminated.

14.
PLoS Pathog ; 14(10): e1007413, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30376582

RESUMEN

Bacterial pathogens are highly adaptable organisms, a quality that enables them to overcome changing hostile environments. For example, Vibrio cholerae, the causative agent of cholera, is able to colonize host small intestines and combat host-produced reactive oxygen species (ROS) during infection. To dissect the molecular mechanisms utilized by V. cholerae to overcome ROS in vivo, we performed a whole-genome transposon sequencing analysis (Tn-seq) by comparing gene requirements for colonization using adult mice with and without the treatment of the antioxidant, N-acetyl cysteine. We found that mutants of the methyl-directed mismatch repair (MMR) system, such as MutS, displayed significant colonization advantages in untreated, ROS-rich mice, but not in NAC-treated mice. Further analyses suggest that the accumulation of both catalase-overproducing mutants and rugose colony variants in NAC- mice was the leading cause of mutS mutant enrichment caused by oxidative stress during infection. We also found that rugose variants could revert back to smooth colonies upon aerobic, in vitro culture. Additionally, the mutation rate of wildtype colonized in NAC- mice was significantly higher than that in NAC+ mice. Taken together, these findings support a paradigm in which V. cholerae employs a temporal adaptive strategy to battle ROS during infection, resulting in enriched phenotypes. Moreover, ΔmutS passage and complementation can be used to model hypermuation in diverse pathogens to identify novel stress resistance mechanisms.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Cólera/microbiología , Interacciones Huésped-Patógeno , Intestinos/microbiología , Mutación , Estrés Oxidativo , Vibrio cholerae/genética , Adaptación Fisiológica , Animales , Catalasa/metabolismo , Cólera/genética , Cólera/patología , Ratones , Especies Reactivas de Oxígeno/metabolismo , Virulencia
15.
Opt Lett ; 45(11): 3022-3025, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32479449

RESUMEN

Free-space quantum key distribution (QKD) based on mobile platforms, such as satellites, drones, and vehicles, is considered a promising way to overcome the rate-distance limit without a quantum repeater. Real-time reference frame calibration is required in most recent implemented polarization encoded QKD systems due to the relative motion between sender and receiver. Although active compensations can be used to calibrate the reference frame, doing so increases the complexity of the system and reduces the key rate. To overcome this problem, the reference-frame-independent (RFI) QKD was proposed in which fixed deviations of the reference frame between the two parties are tolerated automatically. In this Letter, we report the experimental implementation of a time-bin encoded RFI QKD in an urban environment through free space. The quantum bit error rate for key-distill is as low as 1% over a 2 km free-space link with a total equivalent loss of 31.5 dB. Our demonstration shows that a stable RFI QKD can be implemented in the free-space channel.

16.
Opt Lett ; 45(22): 6334-6337, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-33186983

RESUMEN

The source flaw associated with the basis vector in the reference-frame-independent measurement-device-independent quantum key distribution (RFI-MDI-QKD) has not been systematically studied. As a result, it is often assumed that bit error is equal to phase error, which is not theoretically rigorous. Here, we propose a postprocessing method to estimate the phase error rate from the discarded mismatched-basis statistics, where the qubit source does not need to be characterized in detail. The source flaw in the basis vector of the RFI-MDI-QKD protocol can thus be corrected using this method. The numerical simulation results clearly demonstrate that the RFI-MDI-QKD protocol with uncharacterized sources is also insensitive to the misalignment of the reference frame.

17.
Sensors (Basel) ; 20(3)2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32023983

RESUMEN

In airborne passive bistatic radar (PBR), the reference channel toward the opportunity illuminator is applied to receive the direct-path signal as the reference signal. In the actual scenario, the reference signal is contaminated by the multipath signals easily. Unlike the multipath signal in traditional ground PBR system, the multipath signal in the airborne PBR owns not only the time delay but also the Doppler frequency. The contaminated reference signal can cause the spatial-temporal clutter spectrum to expand and the false targets to appear. The performance of target detection is impacted severely. However, the existing blind equalization algorithm is unavailable for the contaminated reference signal in airborne PBR. In this paper, the modified blind equalization algorithm is proposed to suppress the needless multipath signal and restore the pure reference signal. Aiming at the Doppler frequency of multipath signal, the high-order moment information and the cyclostationarity of source signal are exploited to construct the new cost function for the phase constraint, and the complex value back propagation (BP) neural network is exploited to solve the constraint optimization problem for the better convergence. In final, the simulation experiments are conducted to prove the feasibility and superiority of proposed algorithm.

18.
J Cell Biochem ; 120(3): 4444-4450, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30260020

RESUMEN

OBJECTIVE: The current study was designed to investigate the inhibitory effects of ginsenoside Rd (Gs-Rd) on human glioma U251 cells in vitro and its possible underlying mechanisms. METHODS: The groups included blank control group, low concentration Gs-Rd treatment group (20 µM), mid concentration Gs-Rd treatment group (40 µM), and high concentration Gs-Rd treatment group (80 µM). The proliferative activity of human glioma U251 cells was detected by the MTT assay. Flow cytometry was performed to measure cell apoptosis of human glioma U251 cells. In addition, the ELISA assay was used to measure the telomerase activities in different groups on 24 hours, 48 hours, and 72 hours. Furthermore, real-time quantitative polymerase chain reaction (RT-PCR) and Western blot analysis were performed to measure the expression of Bcl-2, human telomerase catalytic subunit (hTERT), and caspase-3 in different groups on 48 hours at both messenger RNA (mRNA) and protein levels. RESULTS: The proliferation of U251 cells was inhibited by Gs-Rd with different concentrations in the dose- and time-dependent manners. In addition, Gs-Rd promoted U251 cell apoptosis rate in a dose-dependent manner. Gs-Rd with different concentrations (20 µM, 40 µM, and 80 µM) significantly enhanced the expression of teleomerase on 24 hours and 48 hours. In addition, Gs-Rd with different concentrations significantly increased caspase-3 and decreased Bcl-2 and hTERT expressions at both mRNA and protein levels. CONCLUSION: The Gs-Rd can remarkably inhibit the proliferation and promote cell apoptosis of human glioma U251 cells. The possible underlying mechanisms could be related to inhibiting telomerase activity, downregulating expression of Bcl-2 and hTERT, and upregulating expression of caspase-3 of human glioma U251 cells.


Asunto(s)
Caspasa 3/biosíntesis , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ginsenósidos/farmacología , Glioma , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Telomerasa/biosíntesis , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Glioma/metabolismo , Glioma/patología , Humanos
19.
J Cell Biochem ; 120(5): 7918-7926, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30426539

RESUMEN

The aim of this study was to investigate the roles of microRNA-383 (miRNA-383) in progression of non-small cell lung cancer (NSCLC) and the potential mechanism. The expressions of miR-383 and Wnt1 protein were detected in lung cancer tissues and cells by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis. After the transfection of miR-383 mimics, si-Wnt1 or miR-383+Wnt1, the viability and apoptosis of NSCLC cells were detected by cell counting kit-8 and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, respectively. The interaction between miR-383 and Wnt1 was investigated by luciferase activity and Western blot analysis. Cells stably transfected with miR-383 mimics were inoculated into the right axillary of nude mice by subcutaneous injection. The tumor volume and weight were measured, and the expressions of miR-383, Wnt1, ß-catenin, and cyclin D1 were detected by qRT-PCR and Western blot analysis. The expression of miR-383 was significantly decreased, and the level of Wnt1 was significantly increased (P < 0.05) in lung cancer tissues and cells. Upregulation of miR-383 or inhibition of Wnt1 expression inhibited the cell viability and induce apoptosis in NSCLC cells. Moreover, Wnt1 was the target gene of miR-383, and its overexpression weakened the regulatory effect of miR-383 on cell viability and apoptosis in NSCLC cells. Besides, the addition of miR-383 decreased the tumor volume and size and inhibited the expressions of Wnt1, ß-catenin, and cyclin D1 at the protein level in nude mice. Collectively, miR-383 induced apoptosis and inhibited cell viability as well as tumorigenic capacity in nude mice via regulating the Wnt/ß-catenin signaling pathway.

20.
Neurourol Urodyn ; 38(1): 22-30, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30350884

RESUMEN

AIM: We conducted a meta-analysis to evaluate the safety and efficacy of mirabegron (50 mg) and solifenacin (5 mg) monotherapy for overactive bladder (OAB) during a 12-week cycle. METHODS: Randomized controlled trials (RCTs) of mirabegron and solifenacin for OAB were searched systematically by using MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. The reference lists of retrieved studies were also perused. RESULTS: Five RCTs which compared solifenacin with mirabegron were studied. Mirabegron achieved the same effect as solifenacin in treating OAB. The mean number of incontinence episodes per 24 h (P = 0.20), mean number of micturitions per 24 h (P = 0.11), mean number of urgency episodes per 24 h (P = 0.23), and mean volume voided per micturition (P = 0.05) suggested that mirabegron and solifenacin had no significant differences in terms of OAB treatment. With regard to drug-related treatment-emergent adverse events (DR-TEAEs) and dry mouth, mirabegron showed better tolerance than solifenacin. Post-voiding residual volume showed a distinct difference in the two groups. Hypertension and tachycardia did not show a significant difference between the two groups, but the pulse rate did. CONCLUSION: The therapeutic effect of mirabegron is similar to that of solifenacin, and mirabegron does not increase the risk of adverse events (AEs).


Asunto(s)
Acetanilidas/uso terapéutico , Succinato de Solifenacina/uso terapéutico , Tiazoles/uso terapéutico , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Agentes Urológicos/uso terapéutico , Acetanilidas/efectos adversos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Succinato de Solifenacina/efectos adversos , Tiazoles/efectos adversos , Agentes Urológicos/efectos adversos
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