Removal of intraglandular calculi in Wharton's duct: clinical outcome and treatment algorithm.

The aim of this study was to propose a treatment strategy for intraglandular submandibular calculi based on calculus site. Seventy-three consecutive patients with impalpable intraglandular submandibular calculi were enrolled retrospectively. The calculi were classified as either post-hilar type, central type, or superficial type. Treatment approaches included transoral duct slitting (TDS), interventional basket retrieval (IBR), intraductal laser lithotripsy (ILL), and transcervical lithotomy (TCL). Complete calculus removal with gland preservation was achieved in 64 patients (87.7%). The success rate for post-hilar, central, and superficial calculi was 86.4% (51/59), 90.9% (10/11), and 100% (3/3), respectively. The treatment approach applied in patients with treatment success was TDS in 32 cases, IBR in 20, ILL in nine, and TCL in three. During follow-up (median 17.3 months), one patient experienced gland atrophy and three had ductal stenosis; the remaining 60 patients (93.8%, 60/64) had good clinical outcomes. In the eight failure cases operated by TDS, the deeply situated calculi could not be detached despite the parenchymal incision in five cases, while the procedure was ceased due to the patient's inability to cooperate in the other three cases. In the remaining failure case, the submandibular gland was sacrificed after calculus extraction via TCL. Application of the proposed treatment algorithm might help preserve gland function in patients with intraglandular submandibular calculi.

[Recent progress in the treatment of intractable sialolithiasis].

Sialolithiasis occurs in approximately 0.45% to 1.20% of the general population. The typical clinical symptom manifests as a painful swelling of the affected glands after a meal or upon salivary stimulation, which extremely affects the life quality of the patients. With the development of sialendoscopy and lithotripsy, most sialoliths can be successfully removed with preservation of the gland. However, sialoliths in the deep hilar-parenchymal submandibular ducts and impacted parotid stones located in the proximal ducts continue to pose great challenges. Our research center for salivary gland diseases (in Peking University School and Hospital of Stomatology) has used sialendoscopy for 17 years and treated >2 000 patients with salivary gland calculi. The success rate was approximately 92% for submandibular gland calculi and 95% for parotid calculi. A variety of minimally invasive surgical techniques have been applied and developed, which add substantial improvements in the treatment of refractory sialolithiasis. Further, the radiographic positioning criteria and treatment strategy are proposed for these intractable stones. Most of the hilar-parenchymal submandibular stones are successfully removed by a transoral approach, including transoral duct slitting and intraductal basket grasping, while a small portion of superficial stones can be removed by a mini-incision in submandibular area. Impacted stones located in the distal third of parotid gland ducts are removed via "peri-ostium incision", which is applied to avoid a cicatricial stenosis from a direct ostium incision. Impacted parotid stones located in the middle and proximal third of the Stensen's duct are removed via a direct mini-incision or a peri-auricular flap. A direct transcutaneous mini-incision is commonly performed under local anesthesia with an imperceptible scar, and is indicated for most of impacted stones located in the middle third, hilum and intraglandular ducts. By contrast, a peri-auricular flap is performed under general anesthesia with relatively larger operational injury of the gland parenchyma, and should be best reserved for deeper intraglandular stones. Laser lithotripsy has been applied in the treatment of sialolithiasis in the past decade, and holmium ∶YAG laser is reported to have the best therapeutic effects. During the past 3 years, our research group has performed laser lithotripsy for a few cases with intractable salivary stones. From our experiences, withdrawal of the endoscopic tip 0.5-1.0 cm away from the extremity of the laser fiber, consistent saline irrigation, and careful monitoring of gland swelling are of vital importance for avoidance of injuries of the ductal wall and the vulnerable endoscope lens during lithotripsy. Larger calculi require multiple treatment procedures. The risk of ductal stenosis can be alleviated by endoscopic dilation. In summary, appropriate use of various endoscopy-assisted lithotomy helps preserve the gland function in most of the patients with refractory sialolithiasis. Further studies are needed in the following aspects: Transcervical removal of intraglandular submandibular stones, intraductal laser lithotripsy of impacted parotid stones and deep submandibular stones, evaluation of long-term postoperative function of the affected gland, et al.

Comparison of two transcutaneous approaches for the removal of impacted parotid stones.

The aim of this study was to comparatively evaluate the indications and treatment outcomes of two transcutaneous approaches for the removal of impacted parotid stones. Sixty-eight consecutive patients with impacted parotid stones underwent endoscopy-assisted lithotomy via a direct mini-incision or a peri-auricular flap. Clinical safety and outcomes were evaluated. Complete stone extraction was achieved in all patients. In the mini-incision group (52 patients), the stones were in the middle third of the main duct in 31 patients, at the hilum in 16, and in the intraglandular duct in five. In the flap group (16 patients), they were in the middle third of the main duct in one patient, at the hilum in seven, and in the intraglandular duct in eight. Salivary fistula occurred in five mini-incision group patients (9.6%) and four flap group patients (25%). The clinical outcome in the mini-incision group (47 patients, median 25 months of follow-up) was good in 28 patients, fair in 13, and poor in six (12.8%). The clinical outcome in the flap group (16 patients, median 84 months of follow-up) was good in nine patients, fair in five, and poor in two (12.5%). The direct mini-incision approach was found to be safe and effective for impacted stones in the middle third, hilum, and proximal third of the main duct, while the peri-auricular approach would be best reserved for deeper intraglandular stones.

Probing Operator Spreading via Floquet Engineering in a Superconducting Circuit.

Operator spreading, often characterized by out-of-time-order correlators (OTOCs), is one of the central concepts in quantum many-body physics. However, measuring OTOCs is experimentally challenging due to the requirement of reversing the time evolution of systems. Here we apply Floquet engineering to investigate operator spreading in a superconducting 10-qubit chain. Floquet engineering provides an effective way to tune the coupling strength between nearby qubits, which is used to demonstrate quantum walks with tunable couplings, reversed time evolution, and the measurement of OTOCs. A clear light-cone-like operator propagation is observed in the system with multiple excitations, and has a nearly equal velocity as the single-particle quantum walk. For the butterfly operator that is nonlocal (local) under the Jordan-Wigner transformation, the OTOCs show distinct behaviors with (without) a signature of information scrambling in the near integrable system.

Long non-coding RNA MNX1-AS1 promotes migration and invasion of esophageal squamous cell carcinoma by upregulating IGF2.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Long non-coding RNA MNX1-AS1 promotes migration and invasion of esophageal squamous cell carcinoma by upregulating IGF2, by D.-N. Zheng, C.-J. Zhang, G.-P. Sun, published in Eur Rev Med Pharmacol Sci 2019; 23 (14): 6179-6185-DOI: 10.26355/eurrev_201907_18431-PMID: 31364117" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/18431.

Long non-coding RNA MNX1-AS1 promotes migration and invasion of esophageal squamous cell carcinoma by upregulating IGF2.

OBJECTIVE: Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor with a high mortality rate and poor prognosis. In this research, we investigated the exact role of long non-coding ribonucleic acids (lncRNA) MNX1-AS1 in the metastasis of ESCC and its possible mechanism. PATIENTS AND METHODS: To investigate the functions of MNX1-AS1 in ESCC, quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was utilized to detect MNX1-AS1 expression of ESCC tissues and cells. Besides, functional assays, including transwell assay and wound healing assay, were performed. Furthermore, qRT-PCR and Western blot assay were used to explore the possible underlying regulatory mechanism. RESULTS: The expression level of MNX1-AS1 was significantly increased in both ESCC tissues sample and cells. Moreover, knockdown of MNX1-AS1 markedly inhibited the migration and invasion of ESCC cells. Besides, knockdown of MNX1-AS1 remarkably down-regulated the mRNA and protein levels of insulin-like growth factor 2 (IGF2). Furthermore, IGF2 expression was positively correlated with MNX1-AS1 expression in ESCC tissues. CONCLUSIONS: MNX1-AS1 serves as a potential oncogene in ESCC, which can significantly promote ESCC cell migration and invasion by up-regulating IGF2. Our findings may provide a new therapeutic target of ESCC.

Liquid-like behaviours of metallic glassy nanoparticles at room temperature.

Direct atomic-scale observations and measurements on dynamics of amorphous metallic nanoparticles (a-NPs) are challenging owing to the insufficient consciousness to their striking characterizations and the difficulties in technological approaches. In this study, we observe coalescence process of the a-NPs at atomic scale. We measure the viscosity of the a-NPs through the particles coalescence by in situ method. We find that the a-NPs have fast dynamics, and the viscosity of the a-NPs exhibits a power law relationship with size of the a-NPs. The a-NPs with sizes smaller than 3 nm are in a supercooled liquid state and exhibit liquid-like behaviours with a decreased viscosity by four orders of magnitude lower than that of bulk glasses. These results reveal the intrinsic flow characteristics of glasses in low demension, and pave a way to understand the liquid-like behaviours of low dimension glass, and are also of key interest to develop size-controlled nanodevices.

Coherent population transfer between uncoupled or weakly coupled states in ladder-type superconducting qutrits.

Stimulated Raman adiabatic passage offers significant advantages for coherent population transfer between uncoupled or weakly coupled states and has the potential of realizing efficient quantum gate, qubit entanglement and quantum information transfer. Here we report on the realization of the process in the superconducting Xmon and phase qutrits--two ladder-type three-level systems in which the ground state population is coherently transferred to the second excited state via the dark state subspace. We demonstrate that the population transfer efficiency is no less than 96% and 67% for the two devices, which agree well with the numerical simulation of the master equation. Population transfer via stimulated Raman adiabatic passage is significantly more robust against variations of the experimental parameters compared with that via the conventional resonant π pulse method. Our work opens up a new venue for exploring the process for quantum information processing using the superconducting artificial atoms.

A cryogen-free dilution refrigerator based Josephson qubit measurement system.

We develop a small-signal measurement system on cryogen-free dilution refrigerator which is suitable for superconducting qubit studies. Cryogen-free refrigerators have several advantages such as less manpower for system operation and large sample space for experiment, but concern remains about whether the noise introduced by the coldhead can be made sufficiently low. In this work, we demonstrate some effective approaches of acoustic isolation to reduce the noise impact. The electronic circuit that includes the current, voltage, and microwave lines for qubit coherent state measurement is described. For the current and voltage lines designed to have a low pass of dc-100 kHz, we show that the measurements of Josephson junction's switching current distribution with a width down to 1 nA, and quantum coherent Rabi oscillation and Ramsey interference of the superconducting qubit can be successfully performed.

Quantum phase diffusion in a small underdamped Josephson junction.

Quantum phase diffusion in a small underdamped Nb/AlO(x)/Nb junction (∼0.4 µm(2)) is demonstrated in a wide temperature range of 25-140 mK where macroscopic quantum tunneling (MQT) is the dominant escape mechanism. We propose a two-step transition model to describe the switching process in which the escape rate out of the potential well and the transition rate from phase diffusion to the running state are considered. The transition rate extracted from the experimental switching current distribution follows the predicted Arrhenius law in the thermal regime but is greatly enhanced when MQT becomes dominant.

A phenomenological approach to the anisotropic magnetoresistance and planar Hall effect in tetragonal La(2/3)Ca(1/3)MnO3 thin films.

A La(2/3)Ca(1/3)MnO(3) Hall bar with its long dimension roughly along the hard axis [110] was fabricated on a single-crystal-like tensilely strained film on SrTiO(3)(001). The anisotropic magnetoresistance (AMR) and planar Hall effect (PHE) have been studied at various external magnetic fields and temperatures. A phenomenological model in the high field limit is developed, and the galvanomagnetic tensor based on a tetragonal symmetry 4/mmm (D(4h)), applicable to epitaxial films on a substrate, has been obtained by expanding the tensor to the sixth order. The derived in-plane transverse resistance R(xy) shows a sin2φ(M) angular dependence, while the longitudinal R(xx) is constituted by not only a two-fold cos2φ(M) term, but also a four-fold cos4φ(M) term due to the square symmetry of the lattice. The model is in good agreement with the experimental results in high fields, while deviations are observed near the {100} easy axis with the decreasing field. Close inspection of the fitting parameters reveals the evolution of these term weights with temperature and magnetic field, which is distinct from conventional ferromagnetic metals and cannot be explained by the phenomenological model. An alternative mechanism for AMR, stemming from the magnetization-induced local orbit deformation through spin-orbit interaction, as previously proposed by O'Donnell et al, may be prevalent in manganites and other systems of complicated crystal structure.

The role of magnetoelastic strain on orbital control and transport properties in an LaTiO(3)-CoFe(2)O(4) heterostructure.

Epitaxial heterostructures of CoFe(2)O(4)/LaTiO(3)/LaAlO(3) have been successfully prepared by using the pulsed laser deposition technique. The magnetoresistance (MR) of the samples is negative and linear with field at H≥2 T, exhibiting no dependence on field directions. Nevertheless, when H<2 T, the MR is negative in a field parallel to the sample plane, but positive in that along the film normal. This novel observed anisotropic MR is explained in terms of the magnetic anisotropy in the ferrimagnetic layer, as well as the magnetoelastic coupling between the two. In fields of different directions, the top CoFe(2)O(4) layer contracts or expands in the sample plane due to the significant magnetostriction effect, changing its resistance accordingly and exerting compressive or tensile strains on the bottom LaTiO(3) layer. Apparently the orbital status and the one-electron bandwidth in the LaTiO(3) layer are altered, which leads to a change in resistance.

Implementation of adiabatic geometric gates with superconducting phase qubits.

We present an adiabatic geometric quantum computation strategy based on the non-degenerate energy eigenstates in (but not limited to) superconducting phase qubit systems. The fidelity of the designed quantum gate was evaluated in the presence of simulated thermal fluctuations in a superconducting phase qubits circuit and was found to be quite robust against random errors. In addition, it was elucidated that the Berry phase in the designed adiabatic evolution may be detected directly via the quantum state tomography developed for superconducting qubits. We also analyze the effects of control parameter fluctuations on the experimental detection of the Berry phase.

Effect of oxygen content on the transport properties of LaTiO(3+ß/2) thin films.

The structural and transport properties of LaTiO(3+ß/2) epitaxial thin films, grown at different oxygen pressures ranging from 6.6 × 10(-4) to 5 Pa, have been investigated. X-ray diffraction peaks of the films shift to lower angles with increasing oxygen pressure, indicative of a variation of the corresponding lattice spacing. All the films show T(2) dependence of resistivity over a large temperature range of ∼200 K, suggesting a band-filling-induced metallic Fermi-liquid behaviour. Upturns in resistivity have been revealed at low temperatures, which could be ascribed to the Anderson-localization effect caused by the cation vacancies. Furthermore, for the thin films grown at high oxygen pressures of 0.5 and 5 Pa, the dependence of resistivity on temperature shows a maximum at high temperatures. The maximum seems to support the argument that transition between t-orbital ordering and disordering plays an important role in dominating transport properties at high temperatures. Carrier density deduced from Hall coefficient increases with the decrease of oxygen content, and shows strong temperature dependence. From the experimental data, it can be asserted that in the LaTiO(3+ß/2) thin films, besides the band filling effect, localization or disorder caused by La and Ti vacancy effects controls the unique transport properties.