Phonon signatures for polaron formation in an anharmonic semiconductor.

Mechanistic studies on lead halide perovskites (LHPs) in recent years have suggested charge carrier screening as partially responsible for long carrier diffusion lengths and lifetimes that are key to superior optoelectronic properties. These findings have led to the ferroelectric large polaron proposal, which attributes efficient charge carrier screening to the extended ordering of dipoles from symmetry-breaking unit cells that undergo local structural distortion and break inversion symmetry. It remains an open question whether this proposal applies in general to semiconductors with LHP-like anharmonic and dynamically disordered phonons. Here, we study electron-phonon coupling in Bi2O2Se, a semiconductor which bears resemblance to LHPs in ionic bonding, spin-orbit coupling, band transport with long carrier diffusion lengths and lifetimes, and phonon disorder as revealed by temperature-dependent Raman spectroscopy. Using coherent phonon spectroscopy, we show the strong coupling of an anharmonic phonon mode at 1.50 THz to photo-excited charge carriers, while the Raman excitation of this mode is symmetry-forbidden in the ground-state. Density functional theory calculations show that this mode, originating from the A1g phonon of out-of-plane Bi/Se motion, gains oscillator strength from symmetry-lowering in polaron formation. Specifically, lattice distortion upon ultrafast charge localization results in extended ordering of symmetry-breaking unit cells and a planar polaron wavefunction, namely a two-dimensional polaron in a three-dimensional lattice. This study provides experimental and theoretical insights into charge interaction with anharmonic phonons in Bi2O2Se and suggests ferroelectric polaron formation may be a general principle for efficient charge carrier screening and for defect-tolerant semiconductors.

Two-Dimensional Moiré Polaronic Electron Crystals.

Two-dimensional moiré materials have emerged as the most versatile platform for realizing quantum phases of electrons. Here, we explore the stability origins of correlated states in WSe_{2}/WS_{2} moiré superlattices. We find that ultrafast electronic excitation leads to partial melting of the Mott states on timescales 5 times longer than predictions from the charge hopping integrals and that the melting rates are thermally activated, with activation energies of 18±3 and 13±2 meV for the one- and two-hole Mott states, respectively, suggesting significant electron-phonon coupling. A density functional theory calculation of the one-hole Mott state confirms polaron formation and yields a hole-polaron binding energy of 16 meV. These findings reveal a close interplay of electron-electron and electron-phonon interactions in stabilizing the polaronic Mott insulators at transition metal dichalcogenide moiré interfaces.

The value of quantitative contrast-enhanced ultrasonography analysis in evaluating central retinal artery microcirculation in patients with diabetes mellitus: comparison with colour Doppler imaging.

AIM: To compare the efficacy of quantitative contrast-enhanced ultrasonography (CEUS) analysis and colour Doppler ultrasound (CDU) in evaluating central retinal artery (CRA) microcirculation in patients with diabetes mellitus (DM). MATERIALS AND METHODS: In this prospective study, a total of 55 patients (98 eyes) with DM were enrolled as the study group. They were compared to 46 age-matched healthy volunteers (92 eyes) who were selected as the control group. Each patient underwent CDU and subsequent CEUS examination. CDU and quantitative CEUS parameters were evaluated. The diagnostic efficiency of the diagnostic performance of CEUS and CDU was evaluated and compared, and the scale thresholds of predictive indicators for the diagnosis of proliferative diabetic retinopathy (PDR) were evaluated using receiver operating characteristics (ROC) curve analyses. RESULTS: Group pairwise comparisons showed that the end diastolic velocity (EDV) and arrival time (AT) of CRA were significant predictors for PDR by CDU and by quantitative CEUS analysis, respectively (all p<0.05). The ROC curve analysis showed that the area under the curve value of AT was significantly higher than that of EDV (0.875 versus 0.634, p=0.0002). Accordingly, an AT cut-off value of 1.07 seconds resulted a sensitivity of 90.62 % and a specificity of 79.31 %. CONCLUSION: Quantitative CEUS analysis can improve the accuracy of clinical staging of diabetic retinopathy for the patients with DM, and the AT showed the best diagnostic efficiency.

Optical spin hall effect in exciton-polariton condensates in lead halide perovskite microcavities.

An exciton-polariton condensate is a hybrid light-matter state in the quantum fluid phase. The photonic component endows it with characters of spin, as represented by circular polarization. Spin-polarization can form stochastically for quasi-equilibrium exciton-polariton condensates at parallel momentum vector k|| ∼ 0 from bifurcation or deterministically for propagating condensates at k|| > 0 from the optical spin-Hall effect (OSHE). Here, we report deterministic spin-polarization in exciton-polariton condensates at k|| ∼ 0 in microcavities containing methylammonium lead bromide perovskite (CH3NH3PbBr3) single crystals under non-resonant and linearly polarized excitation. We observe two energetically split condensates with opposite circular polarizations and attribute this observation to the presence of strong birefringence, which introduces a large OSHE at k|| ∼ 0 and pins the condensates in a particular spin state. Such spin-polarized exciton-polariton condensates may serve not only as circularly polarized laser sources but also as effective alternatives to ultracold atom Bose-Einstein condensates in quantum simulators of many-body spin-orbit coupling processes.

Decoding ultrafast polarization responses in lead halide perovskites by the two-dimensional optical Kerr effect.

The ultrafast polarization response to incident light and ensuing exciton/carrier generation are essential to outstanding optoelectronic properties of lead halide perovskites (LHPs). A large number of mechanistic studies in the LHP field to date have focused on contributions to polarizability from organic cations and the highly polarizable inorganic lattice. For a comprehensive understanding of the ultrafast polarization response, we must additionally account for the nearly instantaneous hyperpolarizability response to the propagating light field itself. While light propagation is pivotal to optoelectronics and photonics, little is known about this in LHPs in the vicinity of the bandgap where stimulated emission, polariton condensation, superfluorescence, and photon recycling may take place. Here we develop two-dimensional optical Kerr effect (2D-OKE) spectroscopy to energetically dissect broadband light propagation and dispersive nonlinear polarization responses in LHPs. In contrast to earlier interpretations, the below-bandgap OKE responses in both hybrid CH3NH3PbBr3 and all-inorganic CsPbBr3 perovskites are found to originate from strong hyperpolarizability and highly anisotropic dispersions. In both materials, the nonlinear mixing of anisotropically propagating light fields results in convoluted oscillatory polarization dynamics. Based on a four-wave mixing model, we quantitatively derive dispersion anisotropies, reproduce 2D-OKE frequency correlations, and establish polarization-dressed light propagation in single-crystal LHPs. Moreover, our findings highlight the importance of distinguishing the often-neglected anisotropic light propagation from underlying coherent quasiparticle responses in various forms of ultrafast spectroscopy.

[Report content and prenatal diagnosis of non-invasive prenatal testing for sex chromosome aneuploidy].

Objective: To analyze the report content, the methods and results of prenatal diagnosis of high risk of sex chromosome aneuploidy (SCA) in non-invasive prenatal testing (NIPT). Methods: A total of 227 single pregnancy pregnant women who received genetic counseling and invasive prenatal diagnosis at Drum Tower Hospital Affiliated to the Medical School of Nanjing University from January 2015 to April 2022 due to the high risk of SCA suggested by NIPT were collected. The methods and results of prenatal diagnosis were retrospectively analyzed, and the results of chromosome karyotype analysis and chromosome microarray analysis (CMA) were compared. The relationship between NIPT screening and invasive prenatal diagnosis was analyzed. Results: (1) Prenatal diagnosis methods for 277 SCA high risk pregnant women included 73 cases of karyotyping, 41 cases of CMA and 163 cases of karyotyping combined with CMA, of which one case conducted amniocentesis secondly for further fluorescence in situ hybridization (FISH) testing. Results of invasive prenatal diagnosis were normal in 166 cases (59.9%, 166/277), and the abnormal results including one case of 45,X (0.4%, 1/277), 18 cases of 47,XXX (6.5%, 18/277), 36 cases of 47,XXY (13.0%, 36/277), 20 cases of 47,XYY (7.2%, 20/277), 1 case of 48,XXXX (0.4%, 1/277), 20 cases of mosaic SCA (7.2%, 20/277), 5 cases of sex chromosome structural abnormality or large segment abnormality (1.8%, 5/277), and 10 cases of other abnormalities [3.6%, 10/277; including 9 cases of copy number variation (CNV) and 1 case of balanced translocation]. Positive predictive value (PPV) for SCA screening by NIPT was 34.7% (96/277). (2) Among the 163 cases tested by karyotyping combined with CMA, 11 cases (6.7%, 11/163) showed inconsistent results by both methods, including 5 cases of mosaic SCA, 1 case of additional balanced translocation detected by karyotyping and 5 cases of additional CNV detected by CMA. (3) NIPT screening reports included 149 cases of "sex chromosome aneuploidy"(53.8%, 149/277), 54 cases of "number of sex chromosome increased" (19.5%, 54/277), and 74 cases of "number of sex chromosome or X chromosome decreased" (26.7%, 74/277). The PPV of "number of sex chromosome increased" and "number of sex chromosome or X chromosome decreased" were 72.2% (39/54) and 18.9% (14/74), respectively, and the difference was statistically significant (χ2=34.56, P<0.01). Conclusions: NIPT could be served as an important prenatal screening technique of SCA, especially for trisomy and mosaicism, but the PPV is comparatively low. More information of NIPT such as the specific SCA or maternal SCA might help improving the confidence of genetic counseling and thus guide clinic management. Multi technology platforms including karyotyping, CMA and FISH could be considered in the diagnosis of high risk of SCA by NIPT.

Disorder of excitons and trions in monolayer MoSe2.

The optical spectra of transition metal dichalcogenide monolayers are dominated by excitons and trions. Here, we establish the dependence of these optical transitions on the disorder from hyperspectral imaging of h-BN encapsulated monolayer MoSe2. While both exciton and trion energies vary spatially, these two quantities are almost perfectly correlated, with spatial variation in the trion binding energy of only ∼0.18 meV. In contrast, variation in the energy splitting between the two lowest energy exciton states is one order of magnitude larger at ∼1.7 meV. Statistical analysis and theoretical modeling reveal that disorder results from dielectric and bandgap fluctuations, not electrostatic fluctuations. Our results shed light on disorder in high quality TMDC monolayers, its impact on optical transitions, and the many-body nature of excitons and trions.

[Analysis of the usage of post-exposure prophylaxis and related factors among men who have sex with men].

A survey was conduct to analyze the usage situation of post-exposure prophylaxis(PEP) and related factors among men who have sex with men(MSM) in 6 cities of Shandong Province. Total of 2 620 subjects, the use ratio was 2.98% (78/2 620). Compared with age≤24 years,monthly income<5 000 yuan,non-commercial sex, non-DU,non-STD,role for being insert in the anal intercourse,MSM was more likely to use PEP with age≥45 years(OR=3.87, 95%CI:1.12-13.36),monthly income≥5 000 yuan(OR=1.87, 95%CI:1.07-3.28),commercial sex (OR=3.13, 95%CI:1.56-6.28), drug users (DUs) (OR=4.63, 95%CI:2.51-8.52),STD patient (OR=2.35,95%CI:1.05-5.27),the mixed sex role group(OR=2.25,95%CI:1.10-4.62).

Solvated Electrons in Solids-Ferroelectric Large Polarons in Lead Halide Perovskites.

Solvation plays a pivotal role in chemistry and biology. A solid-state analogy of solvation is polaron formation, but the magnitude of Coulomb screening is typically an order of magnitude weaker than that of solvation in aqueous solutions. Here, we describe a new class of polarons, the ferroelectric large polaron, proposed initially by Miyata and Zhu in 2018 (Miyata, K.; Zhu, X.-Y. Ferroelectric Large Polarons. Nat. Mater. 2018, 17 (5), 379-381). This type of polaron allows efficient Coulomb screening of an electron or hole by extended ordering of dipoles from symmetry-broken unit cells. The local ordering is reflected in the ferroelectric-like THz dielectric responses of lead halide perovskites (LHPs) and may be partially responsible for their exceptional optoelectronic performances. Despite the likely absence of long-range ferroelectricity in LHPs, a charge carrier may be localized to and/or induce the formation of nanoscale domain boundaries of locally ordered dipoles. Based on the known planar nature of energetically favorable domain boundaries in ferroelectric materials, we propose that a ferroelectric polaron localizes to planar boundaries of transient polar nanodomains. This proposal is supported by dynamic simulations showing sheet-like transient electron or hole wave functions in LHPs. Thus, the Belgian-waffle-shaped ferroelectric polaron in the three-dimensional LHP crystal structure is a large polaron in two dimensions and a small polaron in the perpendicular direction. The ferroelectric large polaron may form in other crystalline solids characterized by dynamic symmetry breaking and polar fluctuations. We suggest that the ability to form ferroelectric large polarons can be a general principle for the efficient screening of charge carriers from scattering with other charge carriers, with charged defects and with longitudinal optical phonons, thus contributing to enhanced optoelectronic properties.

Excitons in strain-induced one-dimensional moiré potentials at transition metal dichalcogenide heterojunctions.

The possibility of confining interlayer excitons in interfacial moiré patterns has recently gained attention as a strategy to form ordered arrays of zero-dimensional quantum emitters and topological superlattices in transition metal dichalcogenide heterostructures. Strain is expected to play an important role in the modulation of the moiré potential landscape, tuning the array of quantum dot-like zero-dimensional traps into parallel stripes of one-dimensional quantum wires. Here, we present real-space imaging of unstrained zero-dimensional and strain-induced one-dimensional moiré patterns along with photoluminescence measurements of the corresponding excitonic emission from WSe2/MoSe2 heterobilayers. Whereas excitons in zero-dimensional moiré traps display quantum emitter-like sharp photoluminescence peaks with circular polarization, the photoluminescence emission from excitons in one-dimensional moiré potentials shows linear polarization and two orders of magnitude higher intensity. These results establish strain engineering as an effective method to tailor moiré potentials and their optoelectronic response on demand.

Author Correction: Excitons in strain-induced one-dimensional moiré potentials at transition metal dichalcogenide heterojunctions.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Diffusivity Reveals Three Distinct Phases of Interlayer Excitons in MoSe_{2}/WSe_{2} Heterobilayers.

Charge separated interlayer excitons in transition metal dichalcogenide heterobilayers are being explored for moiré exciton lattices and exciton condensates. The presence of permanent dipole moments and the poorly screened Coulomb interaction make many-body interactions particularly strong for interlayer excitons. Here we reveal two distinct phase transitions for interlayer excitons in the MoSe_{2}/WSe_{2} heterobilayer using time and spatially resolved photoluminescence imaging: from trapped excitons in the moiré potential to the modestly mobile exciton gas as exciton density increases to n_{ex}∼10^{11} cm^{-2} and from the exciton gas to the highly mobile charge separated electron-hole plasma for n_{ex}>10^{12} cm^{-2}. The latter is the Mott transition and is confirmed in photoconductivity measurements. These findings set fundamental limits for achieving quantum states of interlayer excitons.

Triplet Pair States in Singlet Fission.

This account aims at providing an understanding of singlet fission, i.e., the photophysical process of a singlet state ( S1) splitting into two triplet states (2 × T1) in molecular chromophores. Since its discovery 50 years ago, the field of singlet fission has enjoyed rapid expansion in the past 8 years. However, there have been lingering confusion and debates on the nature of the all-important triplet pair intermediate states and the definition of singlet fission rates. Here we clarify the confusion from both theoretical and experimental perspectives. We distinguish the triplet pair state that maintains electronic coherence between the two constituent triplets, 1(TT), from one which does not, 1(T···T). Only the rate of formation of 1(T···T) is defined as that of singlet fission. We present distinct experimental evidence for 1(TT), whose formation may occur via incoherent and/or vibronic coherent mechanisms. We discuss the challenges in treating singlet fission beyond the dimer approximation, in understanding the often neglected roles of delocalization on singlet fission rates, and in realizing the much lauded goal of increasing solar energy conversion efficiencies with singlet fission chromophores.

The ultrafast Kerr effect in anisotropic and dispersive media.

The ultrafast optical Kerr effect (OKE) is widely used to investigate the structural dynamics and interactions of liquids, solutions, and solids by observing their intrinsic nonlinear temporal responses through nearly collinear four-wave mixing. Non-degenerate mixing schemes allow for background free detection and can provide information on the interplay between a material's internal degrees of freedom. Here, we show a source of temporal dynamics in the OKE signal that is not reflective of the internal degrees of freedom but arises from a group index and momentum mismatch. It is observed in two-color experiments on condensed media with sizable spectral dispersion, a common property near an optical resonance. In particular, birefringence in crystalline solids is able to entirely change the character of the OKE signal via the off-diagonal tensor elements of the nonlinear susceptibility. We develop a detailed description of the phase-mismatched ultrafast OKE and show how to extract quantitative information on the spectrally resolved birefringence and group index from time-resolved experiments in one and two dimensions.

[The application of scales and characteristics of disability in the common genotypes of Charcot-Marie-Tooth disease].

Objective: To analyze the correlations among different common scales for evaluating the severity of the first-visit Charcot-Marie-Tooth disease (CMT), and explore the cross-sectional characteristics of neurological dysfunction in patients with four common genotypes (CMT1A, CMT1X, CMT2A and MPZ-related CMT) at their first visits. Methods: A total of 117 genetically confirmed CMT patients (aged ≥10 years) from the Department of Neurology of the Third Xiangya Hospital from 2009 to 2019 were included in the study, which consisted of 45 CMT1A, 41 CMT1X, 19 CMT2A, and 12 MPZ-related CMT patients. Clinical data of these patients at first visits were collected and neurological deficits were evaluated by Charcot-Marie-Tooth Neuropathy Score (CMTNS), Charcot-Marie-Tooth Examination Score (CMTES), Overall Neuropathy Limitation Scale (ONLS) and Functional Disability Scale (FDS). Spearman's correlation was performed to analyze the relationship between CMTNS, CMTES, ONLS and FDS. The age of onset, duration of disease, scores of CMTNS, CMTES, ONLS and FDS were compared among four genotypes. Results: In the 117 CMT patients, the male to female ratio was 1.79/1, and the age of onset was (19±13) years. The duration of disease was 10(3, 15) years, and the scores of CMTNS, CMTES, ONLS and FDS were 11.4±6.2, 8.8±5.7, 2.7±1.4 and 2.6±1.3, respectively. There was a significant correlation between CMTES, ONLS, FDS and CMTNS in the overall CMT patients and four subtypes respectively (r≥0.40, P<0.05). CMTNS, CMTES and ONLS scores of four subtypes showed positive correlations with duration of disease (P<0.05), but FDS scores of CMT1A, CMT1X and MPZ-related CMT patients exhibited no correlation with duration of disease (P>0.05) at their first visits. The age of onset in CMT2A patients was younger than that of the patients with the other three genotypes (P<0.05), furthermore, the scores of four scales in early-onset CMT2A patients were higher than those of adult-onset type CMT2A patients (CMTNS: P=0.031, CMTES: P=0.048, ONLS: P=0.042, FDS: P=0.047). In CMT1X patients, the males had higher scores than those of females for all four scales (CMTNS: P=0.028, CMTES: P=0.014, ONLS: P=0.023, FDS: P=0.002). Conclusions: CMTNS, CMTES and ONLS could be used in natural history studies and clinical trials according to the different clinical situations. In the four genotypes, CMT2A patients have younger age of onset, and the earlier the age of onset, the severer the dysfunction. Moreover, male CMT1X patients relatively have severer neurological dysfunction than female patients.

[Effects of intermittent hypoxia intestinal bacterial translocation on mesenteric lymph node injury].

Objective: To observe the effect of intermittent hypoxia on intestinal bacterial translocation and mesenteric lymph node (MLN) structure and explore its mechanism. Methods: Twenty-four adult male Wistar rats were randomly divided into an experimental group (HI group) and a control group (UC group), with 12 rats in each. During the experiment, both groups were fed under the same conditions, but the HI group received simulated sleep apnea with hypoxic treatment. On the last day of the 2nd and 4th week of the experiment, 20% urethane(0.7 ml/100g) was used for anesthesia, and MLNs and corresponding small intestinal tissues were aseptically collected.HE staining was used to observe the microscopic changes of the tissues. The lymph node tissue was sent for pathogenic culture. The levels of oxide dismutase (SOD), lipid peroxide (MDA) and reactive oxygen species (ROS) were measured for the extent of oxidative stress. Serum diamine oxidase (DAO) was measured to assess the extent of intestinal mucosal damage. Result: MLNs and their corresponding small intestines were damaged in the HI group as compared to the UC group. With the prolongation of intermittent hypoxic time, the number of germinal centers in MLNs was significantly reduced, with the volume reduced, cortical medullary fusion aggravated, and the area ratio increased. The intestinal tissue showed severe damage to the intestinal epithelium, increased permeability, mucosal edema, and changes of the crypts. At the 4th week, MLNs in the HI group grew Clostridium perfringens under anaerobic conditions, confirming intestinal bacterial translocation. The contents of ROS, SOD and MDA in MLNs of the HI group were significantly higher than those in the UC group (P<0.05). At the 2nd week and the 4th week, the contents of ROS, SOD and MDA were not significantly changed in the UC group(P>0.05). While the content of ROS and MDA in MLNs of the HI group at 4th week was significantly higher than that in the second week (P<0.05), but no change of SOD was observed (P>0.05). Serum DAO levels in the HI group were higher than those in the UC group at week 2 and week 4 (P<0.05), suggesting that the degree of intestinal mucosal injury in the HI group was more serious than that in the UC group. Conclusion: Hypoxic exposure aggravated the degree of oxidative stress in rats. With the prolongation of intermittent hypoxia, the intestinal mucosa of rats was seriously damaged. The intestinal flora shifted to damage the structure of mesenteric lymph nodes, and oxidative stress was further aggravated, which in turn affected the integrity of the intestinal autoimmune function.

Light-Matter Interaction and Lasing in Lead Halide Perovskites.

Lead halide perovskites (LHPs) are attractive material systems for light emission, thanks to the ease and diverse routes of synthesis, the broad tunability in color, the high emission quantum efficiencies, and the strong light-matter coupling which may potentially lead to exciton-polariton condensation. This account contrasts the laser-like coherent light emission from highly lossy Fabry-Perot cavities, formed naturally from LHP nanowires (NWs) and nanoplates (NPs), with highly reflective cavities made of LHP gain media, sandwiched between two distributed Bragg reflector (DBR) mirrors. The mechanism responsible for the operation of conventional semiconductor lasers involves stimulated emission of electron and hole pairs bound by the Coulomb potential, i.e., excitons or, at excitation density above the so-called Mott threshold, an electron-hole plasma (EHP). We discuss how lasing from LHP NWs or NPs likely originates from stimulated emission of an EHP, not excitons or exciton-polaritons. A character central to this kind of lasing is the dynamically changing photonic properties in the naturally formed cavity. In contrast to the more static conditions of a DBR cavity, lasing modes and gain profiles are extremely sensitive to material properties and excitation conditions in an NW/NP cavity. While such unstable photonic cavities pose engineering challenges in the application of NW/NP lasers, they provide excellent probes of many-body physics in the LHP material. For sufficiently strong light-matter coupling expected for LHPs in DBR cavities, an exciton-polariton, i.e., the superposition state between the exciton and the cavity photon, can form. An exciting prospect of strong light-matter coupling is the potential formation of an exciton polariton condensate, which possesses many interesting quantum and nonlinear effects, such as superfluidity, long-range coherence, and laserlike light emission. However, it is difficult to distinguish coherent light from an exciton-polariton condensate and that from conventional stimulated laser emission. Several reports have established the condition of strong coupling for LHPs in DBR cavities. We stress, however, that these studies have not included necessary experiments to unambiguously establish the formation of exciton-polariton condensation, and several experiments and routes of analysis are needed to make a more convincing case for exciton-polariton condensation in LHP based systems. The potential of exciton-polariton condensation expands the horizon of LHP materials from conventional optoelectronics to quantum devices.

[Differential protein expressions in papillary thyroid carcinoma patients with or without Hashimoto's thyroiditis].

Objective: To explore the differential protein expressions in papillary thyroid carcinoma (PTC) with or without Hashimoto's thyroiditis (HT). Methods: Tissue microarray was prepared and the protein expression levels of v-Raf murine sarcoma viral oncogene homolog B1 (BRAF), vascular endothelial growth factor (VEGF), cyclinD1, mesothelial cell (MC) , CD56 and Galectin3 in the PTC tissues with or without HT were detected by immunohistochemical staining. Results: The positive expression rates of BRAF protein in the PTC tissues with or without HT groups were 55.4% (36/65) and 63.6% (42/66), respectively, without significant difference (P=0.336). The positive expression rates of VEGF protein in the PTC tissues with or without HT groups were 25.7% (19/74) and 25.8%(17/66), respectively, without significant difference (P=0.991). The positive expression rates of cyclin D1 protein in the PTC tissues with or without HT groups were 93.4% (71/76) and 97.6% (80/82), without significant difference (P=0.206). The positive expression rates of MC protein in the PTC tissues with or without HT groups were 86.1% (62/72) and 83.5%(71/85), without significant difference (P=0.654). The positive expression rates of Galectin3 protein in the PTC tissues with or without HT groups were 98.7% (76/77) and 97.5% (78/80), without significant difference (P=0.583). The positive expression rates of CD56 in the PTC tissues and adjacent thyroid follicular epithelial cells were 27.4% (32/117) and 65.0% (76/117), respectively, and the difference was statistically significant (P=0.001). The positive expression rates of CD56 in PTC tissues with or without HT were 35.5% (24/68) and 16.5% (13/79), respectively, and the difference was statistically significant (P=0.009). Conclusions: There are no significant differences in the expressions of BRAF, VEGF, CyclinD1, MC and Galectin3 between the PTC tissues with or without HT. However, the significantly differential expression of CD56 between the two group suggests that CD56 may be related to the pathogenesis of PTC with HT. CD56 may be used as a potential molecular marker in PTC diagnosis.

[Efficacy and safety of ruxolitinib in the salvage treatment of chronic graft versus-host disease].

Objective: To investigate the efficacy and safety of low-dose Ruxolitinib in the treatment of patients with chronic graft-versus-host disease (cGVHD) and refractory to the first-line and/or second-line drugs after allogeneic hematopoietic stem cell transplantation. Methods: The clinical data was retrospectively analyzed of patients diagnosed with cGVHD in Anhui Provincial Hospital from July 9, 2018 to May 23, 2019. They were refractory to first-line and second-line drugs and were given a low-dose of Ruxolitinib (a dose of 5 mg twice daily if body weight ≥ 25 kg and 2.5 mg twice daily if body weight<25 kg). There was 2.5 mg reduction per week or every two weeks if the condition improved until withdrawal. The efficacy and safety of Ruxolitinib were retrospectively analyzed weekly or biweekly. If the condition improved, the dosage would be reduced by 2.5 mg weekly or biweekly until discontinuance. Results: A total of 47 patients were included in the study,and the median time of taking Ruxolitinib was 55 (21-154) days. The median time of taking effect was 14(7-28) days. The overall response rate was 87.2% (41/47). The complete response rate was 63.8% (30/47) and the partial response rate was 23.4%(11/47). Among them, 13 cases were mild and the overall response rate was 100%(13/13). Twenty one cases were moderate and the overall response rate was 90.5%(19/21). Thirteen cases were severe and the overall response rate was 69.2%(9/13). The highest overall response rate of all organs the was 100% in the gastrointestinal tract (7/7), and it was 95.8%(23/24) for the skin, 83.3%(5/6) for the liver and 76.9%(10/13) for the lung. The highest rate of complete organ response was 95.8% for skin. Eight patients (17%) developed cytopenia, of which 2(4.2%) were with a decrease of 3-4 degree hemoglobin. Recrudescence of cytomegalovirus occurred in 3 patients (6.4%). After withdrawal of Ruxolitinib, 6 patients (12.7%) had recurrence of cGVHD. The median time to relapse was 35.5(7-90) days. All of their conditions were improved after addition of Ruxolitinib. The median time of response was 7(5-14) days. The median follow-up was 208(33-412) days. Three patients(6.4%) died, and all of them died of severe pulmonary infection. Three patients (6.4%) had relapse of primary disease. The 6-month overall survival rate was 95.7%. Conclusion: Low-dose Ruxolitinib has good efficacy and safety in the treatment of cGVHD.

[Clinical features of anti-myelin oligodendrocyte glycoprotein antibody-associated diseases in children with cortical encephalitis].

Objective: To describe the clinical features of anti-myelin oligodendrocyte glycoprotein (MOG) antibody-positive cortical encephalitis in children. Methods: Patients who were hospitalized in Beijing Children's Hospital from June 2018 to October 2019, with positive MOG antibodies and phenotype of cortical encephalitis were retrospectively analyzed. Cell-based assays (CBAs) were used to test MOG antibodies. Results: Five patients had the phenotype of cortical encephalitis during follow-up, with 3 females and 2 males. The age of onset ranged from 8 years to 12 years and 1 month. At the last follow-up, 3 cases exhibited a monophasic course and 2 cases were with relapse and remission courses. Six out of 8 episodes which had the phenotype of cortical encephalitis presented with seizures, among which 3 episodes had status epilepticus. None had recurrent seizures during remission. Other symptoms included fever (7/8), headache and vomiting (4/8), somnolence (3/8) and hemiplegia (1/8). Unilateral cortical swelling was observed in cerebral magnetic resonance imaging (MRI) of all patients, without any hemorrhage and necrosis. White blood cell (WBC) counts of cerebrospinal fluid increased, ranging from8×10(6)/L to 186×10(6)/L. All patients recovered well after treatment with intravenous immunogloblin and glucocorticoid. Two patients had relapses during follow-up and were additionally treated with mycophenolate mofetil. Conclusions: Anti-MOG antibodies can induce cortical encephalitis. In clinical setting, fever, headache and seizures are common, however, severe consciousness disturbance and local neurological deficits are rare in these patients. Cerebral MRI shows unilateral cortical swelling without any hemorrhage and necrosis. Usually, immunotherapy works well. No patients exist repeated seizures in remission, but some patients may have relapses.