Comprehensive characterization of Epimedium-Rhizoma drynariae herb pair in rat plasma, urine, and feces metabolic profiles by UHPLC-Q-Orbitrap HRMS combined with diagnostic extraction strategy and multicomponent pharmacokinetic study by UHPLC-MS/MS

Epimedium-Rhizoma drynariae (EP-RD) was a well-known herb commonly used to treat bone diseases in traditional Chinese medicine. Nevertheless, there was incomplete pharmacokinetic behavior, metabolic conversion and chemical characterization of EP-RD in vivo. Therefore, this study aimed to establish metabolic profiles combined with multicomponent pharmacokinetics to reveal the in vivo behavior of EP-RD. Firstly, the diagnostic product ions (DPIs) and neutral losses (NLs) filtering strategy combined with UHPLC-Q-Orbitrap HRMS for the in vitro chemical composition of EP-RD and metabolic profiles of plasma, urine, and feces after oral administration of EP-RD to rats were proposed to comprehensively characterize the 47 chemical compounds and the 97 exogenous in vivo (35 prototypes and 62 metabolites), and possible biotransformation pathways of EP-RD were proposed, which included phase I reactions such as hydrolysis, hydrogenation, dehydrogenation, hydroxylation, dehydroxylation, isomerization, and demethylation and phase II reactions such as glucuronidation, acetylation, methylation, and sulfation. Moreover, a UHPLC-MS/MS quantitative approach was established for the pharmacokinetic analysis of seven active components: magnoflorine, epimedin A, epimedin B, epimedin C, icariin, baohuoside II, and icariin II. Results indicated that the established method was reliably used for the quantitative study of plasma active ingredients after oral administration of EP-RD in rats. Compared to oral EP alone, the increase in area under curves and maximum plasma drug concentration (P < 0.05). This study increased the understanding of the material basis and biotransformation profiles of EP-RD in vivo, which was of great significance in exploring the pharmacological effects of EP-RD.

Integrated UHPLC-MS untargeted metabolomics and gut microbe metabolism pathway-targeted metabolomics to reveal the prevention mechanism of Gushudan on kidney-yang-deficiency-syndrome rats

Gushudan (GSD) was a traditional Chinese prescription with the remarkable effect of kidney-tonifying and bone-strengthening. However, the potential prevention mechanisms of the GSD on kidney-yang-deficiency-syndrome (KYDS) and its regulation on gut microbe metabolism still need to be further systematically investigated. This study established untargeted urinary metabolomics based on RP/HILIC-UHPLC-Q-Orbitrap HRMS and combined with multivariate statistical analysis to discover differential metabolites and key metabolic pathways. And the gut microbe metabolism pathway-targeted metabolomic based on HILIC-UHPLC-MS/MS was developed and validated to simultaneously determine 15 gut microbe-mediated metabolites in urine samples from the control group (CON), KYDS model group (MOD), GSD-treatment group (GSD) and positive group (POS). The results showed that a total of 36 differential metabolites were discovered in untargeted metabolomics. These differential metabolites included proline, cytosine, butyric acid and nicotinic acid, which were primarily involved in the gut microbe metabolism, amino acid metabolism, energy metabolism and nucleotide metabolism. And GSD played a role in preventing KYDS by regulating these metabolic pathways. The targeted metabolomics found that the levels of 10 gut microbe-mediated metabolites had significant differences in different groups. Among them, compared with the CON group, the levels of lysine, tryptophan, phenylacetylglycine and hippuric acid were increased in the MOD group, while the levels of threonine, leucine, dimethylamine, trimethylamine, succinic acid and butyric acid were decreased, which verified the disorders of gut microbe metabolism in the KYDS rats and GSD had a significant regulatory effect on this disorder. As well as by comparing analysis, it was found that the experimental results were consistent with previous metabolomics and microbiomics of fecal samples. Therefore, this integrated strategy of untargeted and targeted metabolomics not only elucidated the potential prevention mechanism of GSD on KYDS, but also provided a scientific basis for GSD preventing KYDS via the "gut-kidney" axis.

Chemoselectivity Strategy Based on B-Label Integrated with Tailored COF for Targeted Metabolomic Analysis of Short-Chain Fatty Acids by UHPLC-MS/MS

Chemoselective extraction strategy is an emerging and powerful means for targeted metabolomics analysis, which allows for the selective identification of biomarkers. Short-chain fatty acids (SCFAs) as functional metabolites for many diseases pose challenges in qualitative and quantitative analyses due to their high polarity and uneven abundance. In our study, we proposed the B-labeled method for the derivatization of SCFAs using easily available 3-aminobenzeneboronic acid as the derivatization reagent, which enables the introduction of recognition unit (boric acid groups). To analyze the B-labeled targeted metabolites accurately, cis-diol-based covalent organic framework (COF) was designed to specifically capture and release target compounds by pH-response borate affinity principle. The COF synthesized by the one-step Schiff base reaction possessed a large surface area (215.77 m2/g), excellent adsorption capacity (774.9 μmol/g), good selectivity, and strong regeneration ability (20 times). Combined with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis, our results indicated that the detection sensitivities of SCFAs increased by 1.2-2500 folds compared with unlabeled method, and the retention time and isomer separation were improved. Using this strategy, we determined twenty-six SCFAs in the serum and urine of rats in four groups about osteoporosis and identified important biomarkers related to the tricarboxylic acid cycle and fatty acid metabolism pathways. In summary, UHPLC-MS/MS based on B-labeled derivatization with tailored COF strategy shows its high selectivity, excellent sensitivity, and good chromatographic behavior and has remarkable application prospect in targeted metabolomics study of biospecimens.

[Antioxidant activity of Euryale ferox seed shell extract and its therapeutic effects on oral ulcer in rats]

OBJECTIVE

To investigate the therapeutic effect of Euryale ferox seed shell extract on oral ulcer in rats and its underlying mechanism.

METHODS

The contents of polyphenols and flavonoids in Euryale ferox seed shells were determined by Folin-phenol assay and aluminum nitrate colorimetry, respectively. DPPH·, ABTS+·, ·OH and·O2- scavenging experiments were performed to evaluate the antioxidant activities of Euryale ferox seed shell extract in vitro. In a rat model of oral ulcer induced by burning with glacial acetic acid, the therapeutic effect of Euryale ferox seed shell extract was assessed by detecting changes in serum levels of oxidative factors by enzyme-linked immunosorbent assay (ELISA) and observing pathological changes of the ulcerous mucosa using HE staining; the therapeutic mechanism of the extract was explored by detecting the expression levels of Keap1, Nrf2, Nes-Nrf2 and HO-1 proteins in ulcerous mucosa using Western blotting.

RESULTS

The ethyl acetate extract of Euryale ferox seed shells contained 306.74±1.04 mg/g polyphenols and 23.43±0.61 mg/g flavonoids and had IC50 values for scavenging DPPH· and ABTS+· free radicals of 3.42 ± 0.97 μg/mL and 3.32 ± 0.90 μg/mL, respectively. In the rat models, the ethyl acetate extract significantly ameliorated oral mucosal ulcer, increased serum CAT level, and decreased serum MDA level. The protein expression levels of Nes-Nrf2 and HO-1 were increased and Keap1 protein expression was lowered significantly in the ulcerous mucosa of the rats after treatment with the extract (P<0.05 or 0.01).

CONCLUSION

The therapeutic effect of Euryale ferox seed shell extract on oral ulcers in rats is mediated probably by activation of the Keap1/Nrf2/HO-1 signaling pathway.

Integrated untargeted and targeted testicular metabolomics to reveal the regulated mechanism of Gushudan on the hypothalamic-pituitary-gonadal axis of kidney-yang-deficiency-syndrome rats

Modern studies have shown that neuroendocrine disorders caused by the dysfunction of the hypothalamic-pituitary-gonadal (HPG) axis are one of the important pathogenetic mechanisms of kidney-yang-deficiency-syndrome (KYDS). The preventive effect of Gushudan on KYDS has been reported, but its regulatory mechanisms on the HPG axis have not been elucidated. In this study, we developed an integrated untargeted and targeted metabolomics analysis strategy to investigate the regulatory mechanism of Gushudan on the HPG axis in rats with KYDS. In untargeted metabolomics, we screened 14 potential biomarkers such as glycine, lysine, and glycerol that were significantly associated with the HPG axis. To explore the effect of changes in the levels of potential biomarkers on KYDS, all of them were quantified in targeted metabolomics. With the quantitative results, correlations between potential biomarkers and testosterone, a functional indicator of the HPG axis, were explored. The results showed that oxidative stress, inflammatory response, and energy depletion, induced by metabolic disorders in rats, were responsible for the decrease in testosterone levels. Gushudan improves metabolic disorders and restores testosterone levels, thus restoring HPG axis dysfunction. This finding elucidates the special metabolic characteristics of KYDS and the therapeutic mechanism of Gushudan from a new perspective.

Changes in menopausal symptoms comparing oral estradiol versus transdermal estradiol

OBJECTIVE

This study aimed to compare the efficacy and safety of oral and transdermal estradiol in alleviating menopausal symptoms.

METHOD

A total of 257 recently menopausal women were randomized into two groups. The t-E2 group received transdermal estradiol (2.5 g per day) (n = 128) and the o-E2V group received oral estradiol valerate (2 mg per day) (n = 129) for 24 weeks; both groups received micronized progesterone (200 mg per day). The primary outcome measure is the change in the modified Kupperman Menopausal Index (KMI) after 24 weeks of treatment. Menopausal symptoms were recorded at screening and at 4, 12 and 24 weeks using both the KMI and the Menopause Rating Scale (MRS).

RESULTS

Significant amelioration was observed by KMI and MRS scores for both groups after treatment (p < 0.001). The mean KMI scores showed no difference between the two groups. The mean MRS scores were similar between the two groups at baseline and after 4 weeks of treatment. The results showed statistical differences after 12 weeks and 24 weeks of treatment (p = 0.005 and p = 0.011). Both the after-treatment scores minus the baseline scores of KMI and MRS and the incidence of adverse effects showed no difference between the two groups.

CONCLUSIONS

This study shows that both transdermal and oral estradiol are effective in relieving menopausal symptoms, with little difference in treatment efficacy and safety.

CLINICAL TRIAL NUMBER

ChiCTR2300073146.

[Clinicopathological and prognostic features of subungual melanoma in situ]

Objective: To investigate the clinicopathological characteristics, immunohistochemical profiles, molecular features, and prognosis of subungual melanoma in situ (SMIS). Methods: Thirty cases of SMIS were collected in Fudan University Shanghai Cancer Center, Shanghai, China from 2018 to 2022. The clinicopathological characteristics and follow-up data were retrospectively analyzed. Histopathologic evaluation and immunohistochemical studies were carried out. By using Vysis melanoma fluorescence in situ hybridization (FISH) probe kit, combined with 9p21(CDKN2A) and 8q24(MYC) assays were performed. Results: There were 8 males and 22 females. The patients' ages ranged from 22 to 65 years (median 48 years). All patients presented with longitudinal melanonychia involving a single digit. Thumb was the most commonly affected digit (16/30, 53.3%). 56.7% (17/30) of the cases presented with Hutchinson's sign. Microscopically, melanocytes proliferated along the dermo-epithelial junction. Hyperchromatism and nuclear pleomorphism were two of the most common histological features. The melanocyte count ranged from 30 to 185. Most cases showed small to medium nuclear enlargement (29/30, 96.7%). Pagetoid spread was seen in all cases. Intra-epithelial mitoses were identified in 56.7% (17/30) of the cases. Involvement of nailfold was found in 19 cases, 4 of which were accompanied by cutaneous adnexal extension. The positive rates of SOX10, PNL2, Melan A, HMB45, S-100, and PRAME were 100.0%, 100.0%, 96.0%, 95.0%, 76.9%, and 83.3%, respectively. FISH analysis was positive in 6/9 of the cases. Follow-up data were available in 28 patients, and all of them were alive without disease. Conclusions: SMIS mainly shows small to medium-sized cells. High melanocyte count, hyperchromatism, nuclear pleomorphism, Pagetoid spreading, intra-epithelial mitosis, nailfold involvement, and cutaneous adnexal extension are important diagnostic hallmarks. Immunohistochemistry including SOX10 and PRAME, combined with FISH analysis, is valuable for the diagnosis of SMIS.

Topological super-modes engineering with acoustic graphene plasmons

Acoustic graphene plasmons (AGPs) in a graphene-dielectric-metal structure possess extreme field localization and low loss, which have promising applications in strong photon-matter interaction and integrated photonic devices. Here, we propose two kinds of one-dimensional crystals supporting propagating AGPs with different topological properties, which is confirmed by the Zak phase calculations and the electric field symmetry analysis. Moreover, by combining these two plasmonic crystals to form a superlattice system, the super-modes exist because of the coupling between isolated topological interface states. A flat-like dispersion of super-modes is observed by designing the superlattice. These results should find applications in optical sensing and integrating photonic devices with plasmonic crystals.

Giant Second Harmonic Generation from Membrane Metasurfaces

Metasurfaces have emerged as a fascinating framework for nonlinear optics, which have advantages of a compact footprint and unprecedented flexibility in manipulating light. But their nonlinear responses are generally limited by the short interaction lengths with light. Therefore, further enhancement is highly desired for building high-efficiency nonlinear devices. Here, we experimentally demonstrate a record high second harmonic generation (SHG) efficiency of 2.0 × 10^-4 using lithium niobate (LN) membrane metasurfaces. Benefiting from the large refractive index contrast in the vertical direction and high fabrication quality, distinct spectral resonances and tight field confinements in the LN layer were achieved. Strong SHG peaks resulting from pump resonances of the metasurfaces were observed. Our nonlinear efficiency is more than 2 orders of magnitude larger than previously reported LN metasurfaces. The results inspire a way to improve the efficiency of nonlinear metasurfaces for ultracompact nonlinear light sources in applications of nonlinear holography, Li-Fi, beam shaping, etc.

Error analysis of a rotating-metasurface polarimeter

Polarimeters, which measure the polarization states of light directly, are essentially desired in many areas of science and technology. In our previous work, we have constructed a polarimeter based on a rotating-metasurface, and the polarization Stokes parameters of the light were measured with the known Mueller elements of the metasurface. Here, we further perform the error analysis of the metasurface polarimeter. The errors in the measured Stokes parameters have been formulated for the errors in Mueller elements of the metasurface. This analysis can be used to evaluate and minimize the errors of the metasurface polarimeter.

Neobavaisoflavone improves medial collateral ligament-induced osteoarthritis through repressing the nuclear factor -κB/hypoxia-inducible factor-2α axis

Osteoarthritis (OA) is a chronic inflammatory joint disease. There have been some studies on the treatment of OA with traditional Chinese medicine (TCM). Neobavaisoflavone (NBIF) is an isoflavone isolated from TCM Psoralea corylifolia L (also called 'Buguzhi') and shows anti-inflammatory effects. This study aims to explore the potential role of NBIF in treating OA. The rat chondrocytes were dealt with interleukin-1beta (IL-1β) for inducing an in-vitro OA model and a rat OA model was established by medial collateral ligament resection. Followed by NBIF treatment, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and flow cytometry were performed to evaluate chondrocyte proliferation and apoptosis. The expression of inflammatory factors and oxidative stress factors in chondrocyte medium and rat serum was tested by enzyme-linked immunosorbent assay (ELISA). Hematoxylin-eosin (HE) staining and Safranin O-Fast Green staining were carried out to examine the histopathological changes in knee joints. Caspase-3, nuclear factor-kappaB (NF-κB), and hypoxia-inducible factor-2alpha (HIF-2α) expressions were monitored by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), Western blot, and/or immunohistochemistry. As indicated by the results, NBIF mitigated cartilage matrix degradation and chondrocyte apoptosis in the OA rat model. NBIF hampered IL-1β-mediated cell viability inhibition, apoptosis, inflammatory reactions, and oxidative stress of chondrocytes. Moreover, NBIF suppressed NF-κB phosphorylation and HIF-2α expression. HIF-2α overexpression induced inflammation, oxidative stress, and apoptosis in chondrocytes, while NBIF reversed HIF-2α overexpression-caused chondrocyte damage. Overall, NBIF had antiapoptotic, anti-inflammatory, and antioxidative stress effects in OA models by impeding NF-κB/HIF-2α axis, suggesting that NBIF has potential therapeutic effects in OA.

Intelligent metasurfaces can recognize objects

An on-chip optical neural network is built using metasurfaces, which can recognize objects with high accuracy.

Metasurfaces with high-Q resonances governed by topological edge state

Achieving high-quality (Q)-factor resonances in metasurfaces is essential for various applications, including nano-lasers, nonlinear optics, and quantum optics. In this work, we propose a high-Q metasurface using a topological strategy: constructing the metasurface by stacking two conjugated nanopillar arrays with different topological invariants. Our study shows that a topological edge state steadily appears at the interfaces of the nanopillars, and a sharp transmission resonance with a Q-factor of more than 1000 can be obtained. The sensing application of such high-Q topological metasurface is also demonstrated, whose figure of merit reaches approximately 145. The proposed strategy and underlying theory can open up new avenues to realize ultrasharp resonances, which can promote numerous potential applications, such as biosensing, optical modulation, and slow-light devices.

All-optical modulation of quantum states by nonlinear metasurface

Metasurfaces have proven themselves an exotic ability to harness light at nano-scale, being important not only for classical but also for quantum optics. Dynamic manipulation of the quantum states is at the heart of quantum information processing; however, such function has been rarely realized with metasurfaces so far. Here, we report an all-optical dynamic modulation of the photonic quantum states using the nonlinear metasurface. The metasurface consists of a metallic nanostructure combined with a photoisomerizable azo layer. By tuning the plasmonic resonance through optically switching the azo molecules between their binary isomeric states, we have realized dynamic control of transmission efficiencies of orthogonally polarized photons and also the phase delay between them, thereby an entangled state was efficiently controlled. As an illustration, a quantum state distillation has been demonstrated to recover a Bell state from a non-maximally entangled one to that with fidelities higher than 98%. Our work would enrich the functions of the metasurface in the quantum world, from static to dynamic modulation, making the quantum metasurface going practical.

[Relationship between nutritional factors and clinical outcome in children with tuberculous meningitis]

Objective: To investigate the relationship between nutritional risk status and clinical outcome in children with tuberculous meningitis (TBM). Methods: The clinical data (basic information, clinical symptoms and laboratory test results) of 112 patients with TBM, who were admitted to Department of Pediatric Infectious Diseases of West China Second Hospital of Sichuan University,from January 2013 to December 2020 were retrospectively analyzed. The patients were divided into the nutritional risk group and the non-nutritional risk group according to the assessment of the nutritional risk by the STRONGkids Scale. The variables of basic information, clinical symptoms and laboratory test measurements etc. were compared between the two groups by using Student t test, Rank sum test or Chi-square test. Multivariate Logistic regression analysis were used to analyze nutritional risk factors. Results: Among 112 patient with TBM, 55 were males and 57 females. There were 62 cases in the nutritional risk group and 50 cases in the non-nutritional risk group. The proportion of cases with nutritional risk was 55.4% (62/112). Patients in the nutritional risk who lived in rural areas, had symptoms of brain nerve damage, convulsions, emaciation and anorexia, with a diagnosis time of ≥21 days, and the level of cerebrospinal fluid (CSF) protein were all higher than those in the non-nutritional risk group ((50 cases (80.6%) vs. 32 cases (64.0%), 20 cases (32.3%) vs.8 cases (16.0%), 33 cases (53.2%) vs. 15 cases (30.0%), 30 cases (48.4%) vs. 2 cases (4.0%), 59 cases (95.2%) vs. 1 case (2.0%),41 cases (66.1%) vs.18 cases (36.0%), 1 406 (1 079, 2 068) vs. 929 (683, 1 208) mg/L, χ²=3.91, 3.90, 6.10, 26.72, 98.58, 10.08, Z=4.35, all P<0.05). The levels of serum albumin,hemoglobin,lymphocyte count, white blood cell count, and CSF glucose were significantly lower in patients with nutritional risk ((36±5) vs. (41±4) g/L, (110±17) vs. (122±14) g/L, 1.4 (1.0, 2.0)vs. 2.3 (1.6, 3.8)×10⁹/L, 7.8 (6.3, 10.0)×10⁹ vs. 10.0 (8.3, 12.8)×10⁹/L, 1.0 (0.8, 1.6) vs. 2.1 (1.3, 2.5) mmol/L, t=-6.15, -4.22, Z=-4.86, -3.92, -4.16, all P<0.05).Increased levels of serum albumin (OR=0.812, 95%CI:0.705-0.935, P=0.004) and lymphocyte count (OR=0.609, 95%CI:0.383-0.970, P=0.037) may reduce the nutritional risk of children with TBM; while convulsions (OR=3.853, 95%CI:1.116-13.308, P=0.033) and increased level of CSF protein (OR=1.001,95%CI:1.000-1.002, P=0.015) may increase the nutritional risk of children with TBM. Similarly, the rate of complications and drug-induced liver injury was higher in the nutritional risk group (47 cases (75.8%) vs. 15 cases(30.0%), 31 cases (50.0%) vs.8 cases (16.0%), χ²=23.50, 14.10, all P<0.05). Moreover, the length of hospital stay was also longer in the nutritional risk group ((27±13) vs. (18±7) d, t=4.38, P<0.05). Conclusions: Children with TBM have a high incidence of nutritional risk. Convulsive, the level of serum albumin, the level of lymphocyte count and CSF protein may affect the nutritional risk of children with TBM. The nutritional risk group has a high incidence of complications and heavy economic burden.It is necessary to carry out nutritional screening and nutritional support for children with TBM as early as possible.

Ultra-low-dose estradiol and dydrogesterone: a phase III study for vasomotor symptoms in China

OBJECTIVE

This study aimed to evaluate the efficacy and safety of ultra-low-dose estradiol plus dydrogesterone for vasomotor symptoms in postmenopausal women in China (trial registration CTR20160689).

METHODS

A total of 332 patients were randomized to continuous combined estradiol 0.5 mg + dydrogesterone 2.5 mg or placebo for 12 weeks. The primary efficacy endpoint was change in the number of hot flushes per day from baseline to end of treatment. Secondary efficacy endpoints included change in the number of moderate-to-severe hot flushes per day, menopausal symptoms from baseline and quality of life.

RESULTS

Between baseline and end of treatment, change in the mean number of hot flushes per day was -5.9 (95% confidence interval [CI] - 6.6, -5.2) with estradiol + dydrogesterone and -4.5 (95% CI -5.1, -3.8) with placebo, with a mean difference of -1.4 hot flushes per day (95% CI -2.2, -0.7; p < 0.001). Significant differences in favor of estradiol + dydrogesterone were also observed in several secondary efficacy endpoints. The study treatment was well tolerated.

CONCLUSION

Continuous combined estradiol 0.5 mg + dydrogesterone 2.5 mg reduced hot flushes in postmenopausal women in China. This ultra-low-dose regimen provides an additional option for women experiencing the vasomotor symptoms of menopause. These data are consistent with previous results in other populations.

Linewidth narrowing of aluminum breathing plasmon resonances in Bragg grating decorated nanodisks

Plasmon resonances with high-quality are of great importance in light emission control and light-matter interactions. Nevertheless, inherent ohmic and radiative losses usually hinder the plasmon performance of metallic nanostructures, especially for aluminum (Al). Here we demonstrate a Bragg grating decorated nanodisk to narrow the linewidth of breathing plasmon resonances compared with a commensurate nanodisk. Two kinds of plasmon resonant modes and the corresponding mode patterns are investigated in cathodoluminescence (CL) depending on the different electron bombardment positions, and the experimental results agree well with full wave electromagnetic simulations. Linewidth narrowing can be clearly understood using an approximated magnetic dipole model. Our results suggest a feasible mechanism for linewidth narrowing of plasmon resonances as well as pave the way for in-depth analysis and potential applications of Al plasmon systems.

Nanoinfrared Characterization of Bilayer Graphene Conductivity under Dual-Gate Tuning

Dual-gate tuning on two-dimensional (2D) heterostructures can provide independent control of the carrier concentration and interlayer electrostatic potential, yielding novel electronic and optical properties. In this paper, by utilizing monolayer graphene as both the top gate and a plasmon wavelength magnifier, the optical properties of bilayer graphene (BLG) under dual-gate are quantitatively investigated by nanoinfrared imaging. The hybrid optical modes in the vertically coupled two-layer system are imaged from scattering-type scanning near-field microscopy (s-SNOM). Moreover, plasmon dispersion behaviors under varied dual-gate tuning are explored and explained well with theoretical ones employing tight binding approximation, which reveals the flexibility in individually manipulating the Fermi energy and bandgap. Especially, electron-hole asymmetry in BLG is verified from experiments. Our studies pave route for quantitative near-field investigation of superlattice, topological boundaries, and other emergent phenomena in graphene-based 2D heterostructures.

Tunable terahertz topological edge and corner states in designer surface plasmon crystals

In this work, we study topological edge and corner states in two-dimensional (2D) Su-Schrieffer-Heeger lattices from designer surface plasmon crystals (DSPCs), where the vertical confinement of the designer surface plasmons enables signal detection without the need of additional covers for the sample. In particular, the formation of higher-order topological insulator can be determined by the two-dimensional Zak phase, and the zero-dimensional subwavelength corner states are found in the designed DSPCs at the terahertz (THz) frequency band together with the edge states. Moreover, the corner state frequency can be tuned by modifying the defect strength, i.e., the location or diameter of the corner pillars. This work may provide a new approach for confining THz waves in DSPCs, which is promising for the development of THz topological photonic integrated devices with high compactness, robustness and tunability.

[Clinicopathological features and prognosis of nodal nevi]

Objective: To investigate the clinicopathological characteristics, differential diagnosis and prognosis of nodal nevi (NN). Methods: Eighteen cases of NN diagnosed at Fudan University Shanghai Cancer Center, Shanghai, China from 2009 to 2019 were collected. The clinicopathological characteristics and follow-up data were retrospectively analyzed. Histopathologic evaluation and immunohistochemical studies were carried out. The Vysis Melanoma FISH Probe Kit, combined with 9p21(CDKN2A) and 8q24(MYC) assays were performed in 2 cases. Results: There were 2 males and 16 females in the case series. The age of the patients ranged from 36 to 70 years (average 48.2 years). Fifteen cases located in axillary lymph nodes, 1 in inguinal lymph node, 1 in cervical lymph node, and 1 in external iliac lymph node. NN was found in only one lymph node in each case. Histologically, the nevus cell aggregates were found in capsule of lymph nodes in all cases. Nevus cells grew along the capsule into trabeculae in 8 cases, with 3 of them scattered in parenchyma. In one of these 8 cases, nevus cell aggregates massively occupied the parenchyma of the lymph node. The largest lesions in the 18 NN cases measured from 0.2 to 6.5 mm. All of the NN cases were classified as conventional nevi. The majority of the cases were composed of uniform nevus-like cells and identical to cutaneous pigmented nevi without atypia, necrosis, or mitosis. In the NN case that massively occupied parenchyma, some areas had abundant nevus cells and displayed atypical cytologic features, including increased nucleo-cytoplasmic ratio, small nucleoli, and occasional mitotic figures. Immunohistochemistry was performed in 13 cases. All of them were positive for S-100, SOX10, Melan A, and p16. HMB45 showed weak staining in rare cells of only one case out of 13 cases. Ki-67 labeling index <1% was found in all 13 cases. Additionally, the results of FISH assay were both negative. All patients were followed up for 13 to 129 months (median 31.5 months). Except that one patient died of the salivary gland carcinoma, the other patients all survived without tumor during the follow-up period. Conclusions: NN is a benign melanocytic lesion in lymph node. It is important to distinguish NN from metastatic melanoma when nevus cells occur in parenchyma and subcapsular sinus of lymph nodes, or show some atypical cytologic features. The morphology of bland nevus cells in capsule and trabeculae is a valuable clue. Besides, immunohistochemical profiling and FISH assay are helpful in the differential diagnosis.

[Application of immunohistochemical staining of bcl-2, Ber-EP4, CD10, CK20, and Ki-67 in differential diagnosis between trichoblastoma and basal cell carcinoma]

Objective: To study the utility of immunohistochemistry (IHC) in differential diagnosis between trichoblastoma (TB) and basal cell carcinoma (BCC). Methods: Fifty-eight cases of TB and 40 cases of BCC were collected at Fudan University Shanghai Cancer Center from January 2009 to December 2019 and retrospectively analyzed by IHC for bcl-2, Ber-EP4, CD10, CK20 and Ki-67. Fisher exact test was performed for statistical analysis. Results: Twenty-five (43.1%) TBs and 5 (12.5%) BCCs showed bcl-2 staining in the outermost layer of the epithelial nests, the difference was statistically significant (P<0.01). The proportion of cases with bcl-2 staining>75% of epithelial cells in BCC group was much higher than that in TB group (40% vs. 12.1%; P<0.01). BCC group showed larger proportions with Ber-EP4 staining>75%, 51%-75% of epithelial cells than TB group (12.5% vs. 1.7%, 37.5% vs. 8.6%;P<0.05). Fifty-five (94.8%) TBs demonstrated CD10 expression in the follicular stroma, while only 16 (40.0%) BCCs showed focal or scattered CD10 expression in reactive fibrous stroma (P<0.01). CK20 expression was present in 37 (63.8%) TBs with scattered pattern, but BCCs exhibited no CK20 staining except for only one case (2.5%) showing focal staining (P<0.01). Compared with TB group, the BCC group included more cases with Ki-67 labeling index ≥15% on average and ≥25% in hotspot areas (P<0.05). Conclusion: IHC is helpful in differential diagnosis between TB and BCC. Scattered CK20 staining pattern and stromal CD10 expression support the diagnosis of TB. Bcl-2 staining limited to the outermost layer of the proliferation is more likely to be found in TB. In contrast, Ber-EP4 positivity and higher Ki-67 labeling index tend to be present in BCC.

Machine learning powered ellipsometry

Ellipsometry is a powerful method for determining both the optical constants and thickness of thin films. For decades, solutions to ill-posed inverse ellipsometric problems require substantial human-expert intervention and have become essentially human-in-the-loop trial-and-error processes that are not only tedious and time-consuming but also limit the applicability of ellipsometry. Here, we demonstrate a machine learning based approach for solving ellipsometric problems in an unambiguous and fully automatic manner while showing superior performance. The proposed approach is experimentally validated by using a broad range of films covering categories of metals, semiconductors, and dielectrics. This method is compatible with existing ellipsometers and paves the way for realizing the automatic, rapid, high-throughput optical characterization of films.

Phase-Transition Optical Activity in Chiral Metamaterials

Optical activity from chiral metamaterials is both fundamental in electrodynamics and useful for polarization control applications. It is normally expected that due to infinitesimally small thickness, two-dimensional (2D) planar metamaterials cannot introduce large optical rotations. Here, we present a new mechanism to achieve strong optical rotation up to 90° by evoking phase transition in the 2D metamaterials through tuning coupling strength between meta-atoms. We analytically elucidate such phenomenon by developing a model of phase-transition coupled-oscillator array. And we further corroborate our ideas with both numerical simulations and experiments. Our findings would pave a new way for applying the concept of phase transition in photonics for designing novel optical devices for strong polarization controls and other novel applications.

Validation of reference genes for the normalization of RT-qPCR expression studies on human laryngeal cancer and hypopharyngeal cancer

OBJECTIVE

Selecting stably expressed reference genes is crucial for evaluating real-time quantitative polymerase chain reaction (RT-qPCR) data via the relative quantification method. In the present-day study, our aim was to select optimal reference genes (RGs) for the investigation of target gene (TG) expression profiling in cancerous human laryngeal and hypopharyngeal tissues.

PATIENTS AND METHODS

12 cancerous laryngeal tissues and 10 cancerous hypopharyngeal tissues were investigated. The expression characteristics of 11 reference genes (18S rRNA, GAPDH, B2M, ACTB, TBP, ALAS1, RPL29, HMBS, HPRT1, GUSB, and PUM1), which were commonly used in RT-qPCR for the analysis of gene expression, were investigated using the geNorm, NormFinder, and BestKeeper algorithm programs.

RESULTS

HMBS, ALAS1, and B2M were suggested as optimal RGs for studying human laryngeal and hypopharyngeal cancerous tissues together, laryngeal cancerous tissue by itself, and hypopharyngeal cancerous tissue by itself, respectively. If 2 or more reference genes are needed to achieve better standardization, 3 reference genes can optimally be used in combination to improve the accuracy of relative quantitation normalization. The recommended combinations for studying human laryngeal and hypopharyngeal cancerous tissues together, laryngeal cancerous tissue by itself, and hypopharyngeal cancerous tissue by itself were HMBS + HPRT1 + GUSB, ALAS1 + GUSB + HMBS, and B2M + HPRT1 + TBP, respectively.

CONCLUSIONS

The recommended reference genes could be used to improve the accuracy of gene expression studies on the molecular mechanisms of cancerous human laryngeal and hypopharyngeal tissues. The selected combination of reference genes can effectively improve the accuracy of the relative quantitative diagnosis of gene expression levels, such as messenger RNA, circular RNA, and long-noncoding RNA.

Multifunctional and tunable trigate graphene metamaterial with "Lakes of Wada" topology

Many plasmon-induced transparency (PIT) metamaterials previously reported had limited functions. Their tunabilities were realized by complex discrete structures, which greatly increased the difficulty and cost of device fabrication and adversely affected their resonance characteristics. It is an open question to adjust the Fermi levels of many graphene patterns with only a few in-plane electrodes. We propose and numerically study a novel electrically tunable and multifunctional trigate graphene metamaterial (TGGM) based on the concept of "Lakes of Wada". Benefiting from the trigate regulation, our proposed TGGM turns out to exhibit excellent characteristics, that can not only be used for terahertz band-stop filter, terahertz refractive index sensor, near-field optical switch, slow-light device, but also for double PIT window metamaterial with broad transparency windows and large tunable frequency range.

Diagnostic performance of CT for differentiating peritoneal tuberculosis from peritoneal carcinomatosis: a systematic review and meta-analysis

AIM

To undertake a systematic review and meta-analysis of the diagnostic performance of CT for differentiating peritoneal tuberculosis (PTB) from peritoneal carcinomatosis (PC).

MATERIAL AND METHODS

PubMed, Embase, the Web of Science, and the Cochrane Library were searched for papers published before 23 July 2019. The methodological quality of the studies was analysed. Overlapping descriptors used in different studies to denote the same image finding were subsumed under a single CT feature. Sensitivity, specificity, and positive and negative likelihood ratios were pooled. A summary receiver operating characteristic curve (sROC) was constructed and the area under the curve (AUC) of the included studies was calculated when possible.

RESULTS

Six studies were included and 17 CT features were analysed. The pooled sensitivity and specificity of smooth peritoneal thickening were 59% (95% CI: 52-66%) and 84% (95% CI: 79-88%), respectively. The AUC of smooth peritoneal thickening was 0.83. Omentum line/rim, lymph node necrosis or calcification, and mesenteric macro nodules had a pooled specificity ranging from 95% to 100% and a pooled sensitivity ranging from 12% to 67%. The other 12 signs had a pooled sensitivity ranging from 21% to 79% and a pooled specificity ranging from 19% to 81%. Omentum involvement (cake-like pattern) showed a threshold-effect, so only the AUC (=0.70) was calculated.

CONCLUSIONS

Smooth peritoneal thickening shows fairly good diagnostic accuracy, while omentum rim/line, lymph nodes necrosis or calcification, mesenteric macro nodules have good specificity but limited sensitivity. The informative features summarised in this study may aid clinical practice and future studies.

Ultrastrong coupling of CdZnS/ZnS quantum dots to bonding breathing plasmons of aluminum metal-insulator-metal nanocavities in near-ultraviolet spectrum

Strong coupling originating from excitons of quantum dots and plasmons in nanocavities can be realized at room temperature due to the large electromagnetic field enhancement of plasmons, offering building blocks for quantum information systems, ultralow-power switches and lasers. However, most of the current strong coupling effects were realized by the interaction between excitons and far-field light excited bright plasmon modes in the visible range. Beyond that, there is still a lack of direct imaging of polariton modes at the nanoscale. In this work, by using cathodoluminescence, ultrastrong coupling with Rabi splitting exceeding 1 eV between bonding breathing plasmons of aluminum (Al) metal-insulator-metal (MIM) cavities and excited states of CdZnS/ZnS quantum dots was observed in the near-ultraviolet (UV) spectrum. Further, the hybridization of the QDs excitons and bonding breathing plasmonic modes is verified by deep-subwavelength images of polaritonic modes in real-space. Analytic analysis based on the coupled oscillator model and full-wave electromagnetic simulations is consistent with our experimental results. Our work not only indicates the great potential of electron excited plasmon modes for strong coupling applications, but also extends the polaritonic frequency to the UV range with Al nanocavities.

Tailorable Dynamics in Nonlinear Optical Metasurfaces

Controlling light with light is essential for all-optical switching, data processing in optical communications and computing. Until now, all-optical control of light has relied almost exclusively on nonlinear optical interactions in materials. Achieving giant nonlinearities under low light intensity is essential for weak-light nonlinear optics. In the past decades, such weak-light nonlinear phenomena have been demonstrated in photorefractive and photochromic materials. However, their bulky size and slow speed have hindered practical applications. Metasurfaces, which enhance light-matter interactions at the nanoscale, provide a new framework with tailorable nonlinearities for weak-light nonlinear dynamics. Current advances in nonlinear metasurfaces are introduced, with a special emphasis on all-optical light controls. The tuning of the nonlinearity values using metasurfaces, including enhancement and sign reversal is presented. The tailoring of the transient behaviors of nonlinearities in metasurfaces to achieve femtosecond switching speed is also discussed. Furthermore, the impact of quantum effects from the metasurface on the nonlinearities is introduced. Finally, an outlook on the future development of this energetic field is offered.

Experimental observed plasmon near-field response in isolated suspended graphene resonators

Because of extreme three-dimensional field confinement and easy electrically tunability, plasmons in graphene nanostructures are promising candidates for many applications, such as biosensing, photodetectors and modulators. However, up to now, graphene plasmons have been explored mostly on substrates. Scatterers, corrugations and dopants induced by substrates not only add damping to plasmons but also obscure the intrinsic electronic properties of graphene. In this work, the near-field response of surface plasmons of suspended graphene circular resonators is studied with the scattering-type scanning near-field optical microscopy under different excitation wavelengths, λ = 10.653 and 10.22 μm, respectively. Fundamental and higher order breathing plasmon modes are revealed in real-space with the Fermi energy of graphene of only 0.132 eV. Moreover, the direct experimental evidence on near-field electric tuning in suspended graphene resonators is demonstrated by using back-gate tuning. Our work not only provides a foundation to truly understand the properties of electrons inside pure graphene, but shines light on the applications in optoelectronic devices with suspended two-dimensional materials.

Molecular Typing of Cryptosporidium Species Identified in Fecal Samples of Yaks ( Bos grunniens) of Qinghai Province, China

The frequency of Cryptosporidium infection in yaks from Qinghai province, People's Republic of China, was determined from examination of 1,027 fecal samples collected from 979 adult yaks and 48 yak calves during 4 seasons from 7 geographic areas within the province. PCR amplification of extracted DNA was used to characterize the different species of Cryptosporidium oocysts isolated by fecal examination. Twenty-six (2.53%) positive samples were identified and successfully sequenced: 17 Cryptosporidium ryanae (65.38%), 8 Cryptosporidium bovis (30.77%), and 1 Cryptosporidium baileyi (3.85%). The results of the study indicate that autumn is the primary season for transmission of Cryptosporidium to susceptible yak calves given the favorable temperatures and higher altitude of Qinghai province. To our knowledge, C. baileyi, a species predominately associated with birds (avian hosts), is described for the first time in yaks.

[Clinicopathological features and prognosis of ALK-positive Spitz tumors]

Objective: To investigate the clinicopathologic features and prognosis of ALK-positive Spitz tumors. Methods: Thirteen patients with ALK-positive Spitz tumors diagnosed at Shanghai Cancer Center, Fudan University from October 2016 to December 2017 were collected. All cases were routinely evaluated histopathological features in HE staining and detected ALK protein expression by immunohistochemistry. The ALK fusions of 7 cases were confirmed by fluorescence in situ hybridization (FISH).Follow-up data was collected. Results: The age of patients including 2 males and 11 females ranged from 4 to 47 years (mean 25 years). 12 patients were diagnosed with atypical Spitz tumors and 1 patient was diagnosed with Spitz nevus. Clinically, most lesions presented as papules or nodules, while a few lesions presented as plaques. Histologically, most tumors were exophytic (9/13). More than half of the tumors were amelanotic and the junctional component was mainly composed of melanocytic nests. Kamino bodies were not found. The bases of the tumors were mainly wedge-shaped (5/13) and flat (7/13). Eight tumors displayed mixed cell types, while 5 tumors were composed of only spindle cells. All the tumors showed a plexiform and/or intersecting fascicular growth pattern, and perineural extension was observed in 3 tumors. ALK immunohistochemistry showed diffuse and intense cytoplasmic staining in 13 cases, and 7 of them were detected by FISH to confirm the presence of ALK fusions. All patients were followed up for 7 to 21 months (median=12), with no recurrence or lymph node dissemination. Conclusions: Spitz tumors with ALK fusions have their special histopathologic features.ALK fusions mainly occur in Spitz nevi and atypical Spitz tumors. The follow-up data of the existing literatures and our research indicates that the prognosis of ALK-positive Spitz tumors may be good.

Real-space mapping of mid-infrared near-field of Yagi-Uda antenna in the emission mode

By using transmission-mode, scattering-type scanning near-field optical microscopy, we characterize the mid-infrared near-field properties of a Yagi-Uda antenna in the emission mode. The underlying near-field properties, including the near-field dipole-dipole coupling between antenna elements, are clearly observed. Moreover, even though most of the radiation energy is emitted into the substrate, by adopting two detector antennas, we managed to verify the unidirectionality and frequency-selectivity of the Yagi-Uda antenna in the air side. All the experimental results presented in this work are in good qualitative agreement with our numerical simulations. Our work on the Yagi-Uda antenna could help lead to novel methods for mid-infrared material analysis and bio-sensing. It should also be applicable in all-optical processing like radiation routers or a chromatic discriminator.

Cathodoluminescence nanoscopy of open single-crystal aluminum plasmonic nanocavities

Exact understanding of the plasmon response of aluminum (Al) nanostructures in deep subwavelengths is critical for the design of Al based plasmonic applications, such as the emission control of quantum dots and surface-enhanced resonance Raman scattering in the ultraviolet (UV) range. Here, the plasmonic properties of open triangle cavities patterned by a focused ion beam in single-crystal bulk Al were explored using cathodoluminescence. The resonant modes were determined by experimental spectra and deep subwavelength real-space mode patterns ranging from the visible to the UV, which agreed well with full-wave electromagnetic simulations. The dispersion relation of the cavity modes was consistent with that at the interface between Al and vacuum, showing strong electromagnetic field confinement in the cavities. Open Al triangle cavities provided room for the interaction between optical emitters and confined electromagnetic fields, paving the way for plasmonic devices for a variety of applications, such as plasmonic light-emitting devices or nanolasers in the UV range.

[Lentigo maligna and lentigo maligna melanoma: a clinicopathologic analysis of twenty-four cases]

Objective: To study the clinicopathologic features, differential diagnosis and prognosis of lentigo maligna (LM) and lentigo maligna melanoma (LMM). Methods: Histopathologic evaluation and immunohistochemical study by HRP multimer method were carried out in 24 cases of LM and LMM from 2012 to 2017 at Fudan University Shanghai Cancer Center. The clinical information and follow-up data were analyzed. Results: Of total 24 cases, there were 7 cases of LM and 17 cases of LMM; 10 males and 14 females. The age of patients ranged from 32 to 88 years (mean 67 years). The male-to-female ratio was 1.0∶1.4. Tumors were all located on head and face. Clinically, all patients presented with mottled light brown or sepia macule located on head and face for a long time, and some of them followed by nodules or ulceration within the lesion. The diameter of lesions ranged from 0.5 to 3.0 cm. Microscopically, LM and in-situ component of LMM were all characterized by a predominantly junctional proliferation of atypical melanocytes with marked pleomorphism, frequently extending down the walls of hair follicles and sweat ducts. Multinucleate cells were frequently present. The invasive components of LMM mainly consisted of atypical melanocytic spindle cells (13 cases, 76.5%), and the mean Breslow thickness was 1.2 mm (0.1-2.7 mm). The lesions of LM/LMM were generally associated with severe actinic damage, scattered infiltration of lymphocytes and melanophages. Statistically, the number of cases whose diameter of lesion ≥0.6 cm, mitotic rates ≥4/mm(2) and nests of melanocytes within epidermis in group of LMM were significantly more than those in group of LM. Immunohistochemically, atypical melanocytes in LM and LMM were generally positive for S-100, HMB45, PNL2, Melan A and SOX-10. Follow-up was available in all cases, ranging from 1 to 64 months. Only one out of 23 patients with wide surgical excision had local recurrence, and the remaining 22 patients were all alive with no evidence of disease. One LM patient who was merely treated with biopsy was alive with disease progression after 20 months follow-up. Conclusions: LM/LMM is a special subtype of melanoma predominantly located on the sun-exposed skin of elderly people. Recognition of its specific histologic features can help distinguish with sun-damaged diseases and other subtypes of melanoma. The prognosis of LM/LMM patients treated with surgical excision is considered relatively favorable. However, long term follow-up should be recommended in patients with LM/LMM because of high recurrence rates indicated by previous studies.

Strain sensing based on a microbottle resonator with cleaned-up spectrum

In this Letter, a microbottle-resonator-based strain sensor with individual mode distribution and recognizable resonance spectrum was proposed and demonstrated. A cleaned-up spectrum was achieved by inscribing horizontal microgroove scars close to the bottle center. The inscribing parameters of these grooves were designed according to the field distribution of the modes, and the obtained spectrum showed excellent consistency with theoretical analysis. The shift in the resonance peak with increasing stretching force was investigated, and the corresponding strain sensitivities were 0.085 pm/μϵ for transverse electric polarization and 0.136 pm/μϵ for transverse magnetic polarization, which could be further increased by using materials with smaller elastic moduli.

Near-field imaging of graphene triangles patterned by helium ion lithography

Plasmon nanoresonators in graphene have many applications in biosensing, photodetectors and modulators. As a result, an efficient and precise patterning technique for graphene is required. Helium ion lithography (HIL) emerges as a promising tool for direct writing fabrication because it owns improved fabrication precision compared to electron beam lithography and conventional gallium focused ion beam technique. In this paper, utilizing HIL, a set of graphene triangles are patterned and excellent plasmon response is detected. Particularly, the evolution of breathing mode in these structures is unveiled by scattering-type scanning near-field optical microscopy. Besides, the plasmon response of graphene structures can be efficiently tuned by adjusting the irradiated ion dose during the etching process, which can be explained by the phenomenal simulation model. Our work demonstrates that HIL is a feasible way for precise plasmonic nanostructure fabrication, and can be applied to graphene plasmon control at the nanoscale as well.

Laser direct writing of graphene nanostructures beyond the diffraction limit by graphene oxidation

The fabrication ability of graphene nanostructures is the cornerstone of graphene-based devices, which are of particular interest because of their broad optical response and gate-tunable properties. Here, via laser-induced redox reaction of graphene and silica, we fabricate nano-scale graphene structures by femtosecond laser direct writing. The resolution of destructed graphene lines is far beyond the diffraction limit up to 100 nm with a precision as small as ± 7 nm. Consequently, graphene nanostructures are fabricated precisely and excellent plasmon responses are detected. This novel fabrication method of graphene nanostructures has the advantages of low costs, high efficiency, maskless and especially high precision, which would pave the way for practical application of graphene-based optical and electronic devices.

[Application of sentinel lymph node biopsy in patients with melanoma]

Objective: To investigate the difference between routine hematoxylin-eosin (HE) staining and immunohistochemistry in diagnosing metastatic melanoma in sentinel lymph node (SLN) metastases, and to evaluate the association of SLN tumor burden with the status of non-sentinel lymph nodes (NSLN). Methods: 126 melanoma patients were treated with SLN biopsy and further examined with immunohistochemistry at Fudan University Shanghai Cancer Center between 2010 and 2016, and the status of SLN was respectively estimated by HE stain and immunohistochemistry (S-100 protein, HMB45, Melan A and SOX10). In 39 patients who were treated with complete lymph node dissection, characteristics of SLN tumor burden (maximum diameter of the tumor deposit, tumor penetrative depth and the microanatomic location of the metastasis) and the associations of SLN tumor burden with the involvement of NSLN were all evaluated. Results: Of the total 126 cases, 33 (26.2%) were positive by HE staining and 49 (38.3%) were positive by immunohistochemistry. S-100 protein was positive in 48 out of 49 cases (98.0%). HMB45 was positive in 46 out of 49 cases (93.9%). Melan A was positive in 47 out of 49 cases (96.0%). SOX10 was positive in 8 out of 8 cases. The outcome indicated that the application of immunohistochemistry identified positive SLN missed by HE stain in about 12.1% of cases. Of the 39 patients who were treated with complete lymph node dissection, six showed metastases in NSLN. The frequency of metastases in NSLN was 15.4% (6/39) when SLN was positive. Additionally, the frequency of metastases in NSLN in cases with SLN metastatic deposits ≤2 mm was significantly lower than that in cases with SLN metastatic deposits >2 mm; eight cases with SLN metastatic deposits <0.2 mm had no additional positive NSLN. Conclusions: The findings suggest that immunohistochemistry could effectively improve the detection of positive SLN in melanoma. Cases with SLN metastatic deposits ≤2 mm are less likely to have further metastases in NSLN. There is a need for prospective large-population based studies to identify a subgroup of SLN positive patients who can safely be spared complete lymph node dissection.

[Rare primary proximal epithelioid sarcoma in skull base: clinical analysis of four cases]

Objective: To report the clinical and pathological features of primary proximal epithelioid sarcoma (PES) in skull base. Methods: The clinical and pathological features of four cases of PES in skull base from Sanbo Brain Institute of Capital Medical University and Kunming Sanbo Brain Institute were analysed retrospectively. Results: Three cases was female, and one male, the age ranged from 46 to 52 years.All cases occurred in skull base, and sellar region was the main site of involvement.Under the microscope, the tumor cells characterized by epithelioid cell changes, with or without rhabdoid tumor cells.Mitotic figure was active.Immunohistochemical staining showed that AE1/AE3, EMA and CD34 were variously expression in tumor cells.INI-1 protein was lost in all cases.Three cases were detected by FISH, and INI1 (22q11.2) gene locus was absent in them.Three patients died less than 3 months after surgery, and case 4 was under treatment after five months of surgery. Conclusions: Primary PES in skull base mostly occurs in sellar region and its clinical prognosis is poor.It features with epithelioid/rhabdoid tumor cells with lack granuloma structure as distal ES.It has epithelial and mesenchymal differentiation characteristics.CD34 is always positive.INI1 gene deletion and protein loss expression are characteristic molecular alteration of PES.