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1.
Biomark Med ; : 1-12, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269771

RESUMEN

Aim: To investigate the systemic immune-inflammation index and prognostic immune nutritional index in the prognostic evaluation of oral squamous cell carcinoma.Materials & methods: We analyzed retrospectively the relationship between systemic immune-inflammation index, prognostic immune nutritional index and clinicopathological variables and the overall survival of 262 patients who underwent radical surgery.Results: Multivariate analysis showed high systemic immune-inflammation index (Hazard ratio = 3.062, 95% CI: 1.021-8.251), low prognostic immune nutritional index (Hazard ratio = 0.297, 95% CI: 0.139-0.636), tumor node metastasis classification 3-4 (Hazard ratio = 9.862, 95% CI: 4.658-20.880) patients have worse overall survival.Conclusion: Preoperative systemic immune-inflammation index and prognostic immune nutritional index are independent risk factors for prognostic survival status in oral squamous cell carcinoma.


[Box: see text].

2.
Opt Express ; 32(7): 12601-12608, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571078

RESUMEN

Silicon avalanche photodiode (APD) single-photon detectors in space are continuously affected by radiation, which gradually degrades their dark count performance. From August 2016 to June 2023, we conducted approximately seven years (2507 days) of in-orbit monitoring of the dark count performance of APD single-photon detectors on the Micius Quantum Science Experimental Satellite. The results showed that due to radiation effects, the dark count growth rate was approximately 6.79 cps/day @ -24 °C and 0.37 cps/day @ -55 °C, with a significant suppression effect on radiation-induced dark counts at lower operating temperature. Based on the proposed radiation damage induced dark count annealing model, simulations were conducted for the in-orbit dark counts of the detector, the simulation results are consistent with in-orbit test data. In May 2022, four of these detectors underwent a cumulative 5.7 hours high-temperature annealing test at 76 °C, dark count rate shows no measurable changes, consistent with annealing model. As of now, these ten APD single-photon detectors on the Micius Quantum Science Experimental Satellite have been in operation for approximately 2507 days and are still functioning properly, providing valuable experience for the future long-term space applications of silicon APD single-photon detectors.

3.
Opt Express ; 32(7): 12645-12655, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571082

RESUMEN

The space time frequency transfer plays a crucial role in applications such as space optical clock networks, navigation, satellite ranging, and space quantum communication. Here, we propose a high-precision space time frequency transfer and time synchronization scheme based on a simple intensity modulation/direct detection (IM/DD) laser communication system, which occupies a communication bandwidth of approximately 0.2%. Furthermore, utilizing an optical-frequency comb time frequency transfer system as an out-of-loop reference, experimental verification was conducted on a 113 km horizontal atmospheric link, with a long-term stability approximately 8.3 × 10-16 over a duration of 7800 seconds. Over an 11-hour period, the peak-to-peak wander is approximately 100 ps. Our work establishes the foundation of the time frequency transfer, based on the space laser communication channel, for future ground-to-space and inter-satellite links.

4.
Opt Express ; 32(3): 3989-3996, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297608

RESUMEN

With the rapid development of superconducting quantum computing and the implementation of surface code, large-scale quantum computing is emerging as an urgent demand. In a superconducting computing system, the qubit is maintained in a cryogenic environment to avoid thermal excitation. Thus, the transmission of control signals, which are generated at room temperature, is needed. Typically, the transmission of these signals to the qubit relies on a coaxial cable wiring approach. However, in a large-scale computing system with hundreds or even thousands of qubits, the coaxial cables will pose great space and heat load to the dilution refrigerator. Here, to tackle this problem, we propose and demonstrate a direct-modulation-based optical transmission line. In our experiment, the average single-qubit XEB error and control error are measured as 0.139% and 0.014% separately, demonstrating the feasibility of the optical wiring approach and paving the way for large-scale superconducting quantum computing.

5.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37796097

RESUMEN

Quantum key distribution (QKD) research has yielded highly fruitful results and is currently undergoing an industrialization transformation. In QKD systems, electro-optic modulators are typically employed to prepare the required quantum states. While various QKD systems operating at GHz repetition frequency have demonstrated exceptional performance, they predominantly rely on instruments or printed circuit boards to fulfill the driving circuit function of the electro-optic modulator. Consequently, these systems tend to be complex with low integration levels. To address this challenge, we have introduced a modulator driver integrated circuit in 0.18 µm SiGe BiCMOS technology. The circuit can generate multiple-level driving signals with a clock frequency of 1.25 GHz and a rising edge of ∼50 ps. Each voltage amplitude can be independently adjusted, ensuring the precise preparation of quantum states. The measured signal-to-noise ratio was more than 17 dB, resulting in a low quantum bit error rate of 0.24% in our polarization-encoding system. This work will contribute to the advancement of QKD system integration and promote the industrialization process in this field.

6.
Phys Rev Lett ; 131(10): 100802, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37739363

RESUMEN

Measurement-device-independent quantum key distribution (MDI QKD) provides immunity against all attacks targeting measurement devices. It is essential to implement MDI QKD in the future global-scale quantum communication network. Toward this goal, we demonstrate a robust MDI QKD fully covering daytime, overcoming the high background noise that prevents BB84 protocol even when using a perfect single-photon source. Based on this, we establish a hybrid quantum communication network that integrates free-space and fiber channels through Hong-Ou-Mandle (HOM) interference. Additionally, we investigate the feasibility of implementing HOM interference with moving satellites. Our results serve as a significant cornerstone for future integrated space-ground quantum communication networks that incorporate measurement-device-independent security.

7.
Patient Prefer Adherence ; 17: 1689-1703, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37484742

RESUMEN

Background and Purpose: The purpose of this study was to investigate the relationships among attitudes and practice about oral health, socioeconomic status, subjective oral symptoms, self-rated oral health, and oral health-related quality of life (OHRQoL) in a group of people from eastern China. Methods: Between January 2021 to February 2022, 2502 (87.4%) of the 2863 participants completed an online questionnaire. OHRQoL, Socio-demographics characteristics, attitudes and practice toward oral health, self-rated oral health and subjective oral symptoms were all covered by the questionnaires. Based on the hypothetical model, structural equation modeling with the bootstrap method was used to examine the interactions and the strength of the correlations between the measured variables. Results: The final model demonstrated acceptable data fit. Socioeconomic status (ß = -0.051), attitudes (ß = -0.100) and practice (ß = -0.127) toward oral health, self-rated oral health (ß = -0.493) and subjective oral symptoms (ß = 0.294) were all significantly correlated with OHRQoL. Socioeconomic status was directly linked to attitudes (ß = 0.046) and practice (ß =0.070) about oral health, and attitudes play the role of intermediary between practice and socioeconomic status (ß = 0.018). OHRQoL was indirectly linked with attitudes mediated by practice (ß = -0.092), practice mediated by subjective oral symptoms (ß = -0.107), subjective oral symptoms mediated by self-rated oral health (ß = 0.031). OHRQoL was correlated with income, educational level, and socioeconomic status. Self-rated oral health was related to educational level and socioeconomic status. Conclusion: In a sample of eastern China residents, OHRQoL was influenced by socioeconomic status, attitudes and practice toward oral health, subjective oral symptoms, and self-rated oral health.

8.
Oral Health Prev Dent ; 21(1): 25-32, 2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36727835

RESUMEN

PURPOSE: To evaluate the relationship between self-rated oral health, subjective oral conditions, oral health behaviours, and oral health-related quality of life (OHRQoL) in Chinese college students. MATERIALS AND METHODS: An online cross-sectional survey was conducted, inviting college students from eastern China to participate. A total of 1708 participants were included. A structural equation model was constructed to explain and assess the associations among self-rated oral health, subjective oral conditions, oral health behaviours, and OHRQoL. RESULTS: Self-rated oral health had a direct positive effect on subjective oral conditions and OHRQoL. Oral health behaviours had direct negative impacts on subjective oral conditions and OHRQoL as well as on tooth condition perception and oral health interventions. Subjective oral conditions had a direct positive effect on OHRQoL. There was a positive correlation between oral health behaviours and self-rated oral health. In addition, subjective oral conditions partially mediated both the effect of oral health behaviours on OHRQoL and the effect of self-rated oral health on OHRQoL. CONCLUSION: There were influential associations between self-rated oral health, subjective oral conditions, oral health behaviours, and OHRQoL among college students in eastern China. Making the most of their association can be a guide to radically improving the oral health of college students.


Asunto(s)
Enfermedades de la Boca , Salud Bucal , Humanos , Calidad de Vida , Estudios Transversales , Autoevaluación Diagnóstica , Conductas Relacionadas con la Salud , Encuestas y Cuestionarios
9.
Nature ; 610(7933): 661-666, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36198794

RESUMEN

Networks of optical clocks find applications in precise navigation1,2, in efforts to redefine the fundamental unit of the 'second'3-6 and in gravitational tests7. As the frequency instability for state-of-the-art optical clocks has reached the 10-19 level8,9, the vision of a global-scale optical network that achieves comparable performances requires the dissemination of time and frequency over a long-distance free-space link with a similar instability of 10-19. However, previous attempts at free-space dissemination of time and frequency at high precision did not extend beyond dozens of kilometres10,11. Here we report time-frequency dissemination with an offset of 6.3 × 10-20 ± 3.4 × 10-19 and an instability of less than 4 × 10-19 at 10,000 s through a free-space link of 113 km. Key technologies essential to this achievement include the deployment of high-power frequency combs, high-stability and high-efficiency optical transceiver systems and efficient linear optical sampling. We observe that the stability we have reached is retained for channel losses up to 89 dB. The technique we report can not only be directly used in ground-based applications, but could also lay the groundwork for future satellite time-frequency dissemination.

10.
Phys Rev Lett ; 128(17): 170501, 2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35570417

RESUMEN

Long-distance quantum state transfer (QST), which can be achieved with the help of quantum teleportation, is a core element of important quantum protocols. A typical situation for QST based on teleportation is one in which two remote communication partners (Alice and Bob) are far from the entanglement source (Charlie). Because of the atmospheric turbulence, it is challenging to implement the Bell-state measurement after photons propagate in atmospheric channels. In previous long-distance free-space experiments, Alice and Charlie always perform local Bell-state measurement before the entanglement distribution process is completed. Here, by developing a highly stable interferometer to project the photon into a hybrid path-polarization dimension and utilizing the satellite-borne entangled photon source, we demonstrate proof-of-principle QST at the distance of over 1200 km assisted by prior quantum entanglement shared between two distant ground stations with the satellite Micius. The average fidelity of transferred six distinct quantum states is 0.82±0.01, exceeding the classical limit of 2/3 on a single copy of a qubit.

11.
Appl Opt ; 61(3): 812-817, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35200788

RESUMEN

Spectral filtering is essential in daytime quantum key distribution (QKD), which can suppress the strong background noise caused by scattered solar irradiation. An integrated Fabry-Perot filter is implemented based on a scheme that combines a Fabry-Perot etalon and a dense-wavelength-division-multiplex filter for narrow linewidth filtering and broad-spectrum noise suppression, respectively. This filter is integrated into a butterfly package with single-mode fibers for optical input and output, thereby enhancing high robustness and ease of use. The measurement results show that the filter has a linewidth of 25.6 pm, a noise suppression of over 44.7 dB ranging between 1380-1760 nm, an optical efficiency of 74.5% with variation less than 0.9% in 120 min, and a polarization fidelity after compensation exceeding 99.9%. The ability of fine-tuning the central wavelength with 9.5 pm/°C makes it very suitable for satellite-based applications under the Doppler effect. Further analysis is also given to demonstrate the prospects of applying this filter in future satellite-based daytime QKD applications.

12.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-920550

RESUMEN

Objective@#To investigate the effect of elective neck dissection on the 5-year survival rate of patients with early oral squamous cell carcinoma.@*Methods@#The data of 100 patients with early oral squamous cell carcinoma (cT1-2N0M0) were retrospectively analyzed. In 61 cases, the primary tumor was subjected to elective neck dissection (END). Neck observation and follow-up (NOF) were performed in 39 cases with enlarged resection of primary lesions. Clinicopathological data such as pT staging, pathology classification,the rate of cervical lymph node metastasis and the 5-year survival rate of the patients were statistically analyzed.@*Results@#The 5-year survival rates of the END and NOF groups were 86.9% and 69.2%, respectively, and the difference was statistically significant (P=0.028). END treatment was significantly better than NOF in controlling cervical lymph node metastasis in early oral squamous cell carcinoma (P=0.009). After stratified analysis of histopathological features, the 5-year survival rate of patients with pathological T2 (pT2) stage OSCC in the END group was significantly higher than that in the NOF group (P=0.020). The 5-year survival rate of patients with moderate and poorly differentiated pathological grade OSCC in the END group was significantly higher than that in the NOF group (P=0.013). @*Conclusion @# END is effective for the management of the cervical lymph node metastasis rate in early OSCC patients. For patients with pT2 stage or low differentiation pathological grade, active END can significantly improve the 5-year survival rate.

13.
Opt Express ; 29(19): 29595-29603, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34614701

RESUMEN

Time synchronization is crucial for quantum key distribution (QKD) systems. In order to compensate for the time drift caused by the Doppler effect and adapt to the unstable optical link in satellite-to-ground QKD, previous demonstrations generally adopted synchronization methods requiring additional hardware. In this paper, we present a novel synchronization method based on the detected quantum photons, thus simplifying additional hardware and reducing the complexity and cost. This method adopts target frequency scanning to realize fast frequency recovery, utilizes polynomial fitting to compensate for the Doppler effect, and takes use of the vacuum state in the decoy-state BB84 protocol to recover the time offset. This method can avoid the influence of synchronization light jitter, thus improving the synchronization precision and the secure keys as well. Successful satellite-to-ground QKD based on this new synchronization scheme has been conducted to demonstrate its feasibility and performance. The presented scheme provides an effective synchronization solution for quantum communication applications.

14.
Appl Opt ; 60(16): 4787-4792, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34143043

RESUMEN

Time synchronization is essential for quantum key distribution (QKD) applications, not only in fiber links and terrestrial free-space links but also in satellite-to-ground links. To compensate for the time drift caused by the Doppler effect and adapt to the unstable optical link in satellite-to-ground QKD, previous demonstrations adopted a two-stage solution, combining a global navigation satellite system (GNSS) and light synchronization. In this paper, we propose a novel aperiodic synchronization scheme that can achieve high-precision time synchronization by encoding time information into pseudo-random laser pulse positions. This solution can simplify the use of GNSS hardware, thus reducing the complexity and cost of the system. Successful experiments have been conducted to demonstrate the feasibility and robustness of the presented scheme, resulting in a synchronization precision of 208-222 ps even when 90% of the light signals are lost. Further analysis of the Doppler effect between the satellite and the ground station is also given. The presented robust aperiodic synchronization can be widely applied to future satellite-based quantum information applications.

15.
BMC Oral Health ; 21(1): 99, 2021 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-33676475

RESUMEN

BACKGROUND: This study aimed to evaluate the associations among oral health-related knowledge, attitudes, practice (KAP), self-rated oral health and oral health-related quality of life (OHRQoL) among Chinese college students. METHODS: Of the 2000 participants, 1751 (87.55%) students answered an online questionnaire between October 2019 and January 2020. The questionnaire included demographic characteristics, knowledge, attitudes, and practice related to oral health, self-rated oral health, and OHRQoL. Structural equation modelling was applied to assess the associations among study variables. RESULTS: Among the total students, oral health-related knowledge and attitudes were satisfactory, while the oral health practice was not optimistic. The final model showed satisfactory fitness to the data. Oral health knowledge was associated with attitudes directly and positively. Attitudes toward oral health had a direct and positive effect on practice. Oral health knowledge had an indirect effect on practice through attitudes. Oral health practice was directly associated with self-rated oral health. Oral health knowledge, practice, and self-rated oral health all affected OHRQoL directly and positively, while attitudes had a direct negative impact on OHRQoL. CONCLUSIONS: OHRQoL was influenced by oral health knowledge, attitudes, practice, and self-rated oral health. Our findings support the KAP theory. Limitations of the KAP model were also found.


Asunto(s)
Salud Bucal , Calidad de Vida , China , Estudios Transversales , Conocimientos, Actitudes y Práctica en Salud , Humanos , Análisis de Clases Latentes , Estudiantes , Encuestas y Cuestionarios
16.
Nature ; 589(7841): 214-219, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408416

RESUMEN

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

17.
J Obstet Gynaecol Res ; 47(2): 583-591, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33145891

RESUMEN

AIM: Breast cancer is the most frequent malignant tumor among Chinese women. Breast self-examination (BSE) is a simple, effective method for early detection of screening and it is essential for the prevention and control of breast cancer. The aim of this study was to create a hypothetical model to determine the factors influencing women's BSE behavior in Eastern China. METHODS: A survey was conducted using an online questionnaire and targeting 1200 women aged 18-70 years in Eastern China. Collected data were analyzed using ibm spss 25.0 and amos 24.0 software. RESULTS: The final model showed a desirable fitness to sample data. A direct positive relationship exists between knowledge on risk factors and BSE. A direct positive association was found between positive attitudes and BSE, while negative attitudes have a direct negative impact on BSE. Objective factors not only had a significant direct impact on BSE, but also directly affected the positive attitudes. Positive attitudes play an intermediary role between objective factors and BSE. CONCLUSION: Knowledge on risk factors about breast cancer, attitudes toward BSE and objective factors are new predictors which may influence BSE by using the structural equation modeling method.


Asunto(s)
Neoplasias de la Mama , Autoexamen de Mamas , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/prevención & control , China/epidemiología , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Análisis de Clases Latentes , Encuestas y Cuestionarios
18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(11): 1417-1422, 2020 Nov 15.
Artículo en Chino | MEDLINE | ID: mdl-33191700

RESUMEN

OBJECTIVE: To investigate the application value of contrast-enhanced ultrasound (CEUS) technique to assist the repair of oral and maxillofacial defects by superficial inferior epigastric artery perforator flap. METHODS: Sixteen oral cancer patients, 10 males and 6 females, who were to undergo superficial inferior epigastric artery perforator flap repair between June 2018 and February 2020, were selected, with an average age of 55.8 years (range, 24-77 years). There were 13 cases of squamous cell carcinoma, 2 cases of adenoid cystic carcinoma, and 1 case of mucinous epidermis-like carcinoma. The color Doppler ultrasound (CDUS) and CEUS were used to screen the superficial inferior epigastric artery, assisted in the design of the flap, and compared it with the actual intraoperative exploration. The sensitivity, specificity, positive predictive value, and negative predictive value of CEUS and CDUS examinations were analyzed. Fourteen of 16 patients were repaired with superficial inferior epigastric artery perforator flap, and 2 patients were repaired with superficial iliac artery flap because the source artery was not found. After surgery, regular follow-up was performed to check for disease recurrence and metastasis and to evaluate the appearance of the patien's donor area, the recovery of transoral feeding function, and the presence of complications. RESULTS: Comparison of preoperative CDUS and CEUS findings and intraoperative exploration showed that CEUS had 100% sensitivity, specificity, positive predictive value, and negative predictive value for vascular exploration of the superficial inferior epigastric artery perforator flap, compared with 57%, 100%, 100%, and 25% for CDUS. The preoperative CDUS identified 25 penetrating vessels in 14 cases repaired with superficial inferior epigastric artery flaps. All vessel signals were enhanced by CEUS enhancement, and an additional 11 penetrating vessels were identified confirmed intraoperatively. The preoperative CEUS measurements of the initial diameter of superficial arteries in the abdominal wall were significantly higher than both CDUS and intraoperative measurements ( P<0.05); the difference in peak systolic velocity between CEUS and CDUS measurements was significant ( t=3.708, P=0.003). One case of superficial epigastric artery perforator flap developed venous embolism crisis at 48 hours after operation, the wound healing delayed. The other incisions in donor sites healed by first intention. All the patients were followed up 3-12 months, with an average of 8 months. No recurrence or metastasis appeared during the follow-up. There was no serious complications such as abdominal wall hernia, the location of abdominal scarring was hidden, and transoral feeding was resumed. CONCLUSION: The superficial inferior epigastric artery perforator flap with small injury in supply area and hidden scar location is a better choice for repairing oral and maxillofacial defects. The use of CEUS technique to assist the preoperative design of the superficial inferior epigastric artery perforator flap has good feasibility and high accuracy.


Asunto(s)
Pared Abdominal , Colgajo Perforante , Procedimientos de Cirugía Plástica , Adulto , Anciano , Arterias Epigástricas/diagnóstico por imagen , Arterias Epigástricas/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Adulto Joven
19.
mSphere ; 5(4)2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32641425

RESUMEN

Streptococcus mutans is one of the primary pathogens responsible for the development of dental caries. Recent whole-genome sequencing (WGS)-based core genome multilocus sequence typing (cgMLST) approaches have been employed in epidemiological studies of specific human pathogens. However, this approach has not been reported in studies of S. mutans Here, we therefore developed a cgMLST scheme for S. mutans We surveyed 199 available S. mutans genomes as a means of identifying cgMLST targets, developing a scheme that incorporated 594 targets from the S. mutans UA159 reference genome. Sixty-eight sequence types (STs) were identified in this cgMLST scheme (cgSTs) in 80 S. mutans isolates from 40 children that were sequenced in this study, compared to 35 STs identified by multilocus sequence typing (MLST). Fifty-six cgSTs (82.35%) were associated with a single isolate based on our cgMLST scheme, which is significantly higher than in the MLST scheme (11.43%). In addition, 58.06% of all MLST profiles with ≥2 isolates were further differentiated by our cgMLST scheme. Topological analyses of the maximum likelihood phylogenetic trees revealed that our cgMLST scheme was more reliable than the MLST scheme. A minimum spanning tree of 145 S. mutans isolates from 10 countries developed based upon the cgMLST scheme highlighted the diverse population structure of S. mutans This cgMLST scheme thus offers a new molecular typing method suitable for evaluating the epidemiological distribution of this pathogen and has the potential to serve as a benchmark for future global studies of the epidemiological nature of dental caries.IMPORTANCEStreptococcus mutans is regarded as a major pathogen responsible for the onset of dental caries. S. mutans can transmit among people, especially within families. In this study, we established a new epidemiological approach to S. mutans classification. This approach can effectively differentiate among closely related isolates and offers superior reliability relative to that of the traditional MLST molecular typing method. As such, it has the potential to better support effective public health strategies centered around this bacterium that are aimed at preventing and treating dental caries.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Genoma Bacteriano , Tipificación de Secuencias Multilocus/métodos , Streptococcus mutans/clasificación , Streptococcus mutans/genética , Preescolar , China/epidemiología , Genotipo , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/transmisión , Humanos , Filogenia , Reproducibilidad de los Resultados , Secuenciación Completa del Genoma
20.
J Colloid Interface Sci ; 580: 171-179, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32683115

RESUMEN

Realizing highly effective and selective enrichment of radioactive Cs(I) in complex environmental systems and exploring the microscale adsorption mechanism of Cs(I) on adsorbing material is the key point for developing highly efficient materials for Cs(I) adsorption. In addition, the low cytotoxicity of materials is essential for practical applications and environmental protection. In this study, the controlled assembly of bentonite carrier with a highly selective substance of Cs(I) is prepared by in-situ synthesis method in order to construct a low-toxic functional clay material with high adsorption capacity and selectivity of Cs(I) in complex environmental systems. The efficiency of the zinc hexacyanoferrate(III)-grafted magnetic bentonite (denoted as ZHF/MB) composite was evaluated in adsorption isotherm studies, kinetics analyses, and selectivity tests by using the batch technique. The toxicity of the ZHF/MB composite was evaluated through in vitro cytotoxicity assays using human hepatic cells (HepG2 cells). The results revealed that the ZHF/MB composite had not only a higher adsorption capacity (1.638 mmol/g, 60 °C) for Cs+ ions than a number of other natural and manmade materials but also no cytotoxicity in human cells. In addition, the ZHF/MB composite showed excellent selectivity for Cs+ with a removal efficiency of over 90% from solution (m/V = 0.4 g/L, [Mn+]initial = 10 mg/L, Mn+= Cs+, Ni2+,Sr2+, Co2+). The promising safe toxicology profile, remarkable Cs+ adsorption efficiency, and excellent selectivity of the ZHF/MB composite demonstrate its great potential for using as a decorporation agent for radioactive cesium remediation. The implementation of this research will provide new adsorption materials and method for radioactive Cs(I) waste management.

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