Short-term clinical outcomes and five-year survival analysis of laparoscopic-assisted transanal natural orifice specimen extraction versus conventional laparoscopic surgery for sigmoid and rectal cancer: a single-center retrospective study

Background

The cosmetic benefits of natural orifice specimen extraction (NOSE) are easily noticeable, but its principles of aseptic and tumor-free procedure have caused controversy.

Methods

We conducted a retrospective analysis of the clinical data of patients who underwent laparoscopic-assisted transanal NOSE or conventional laparoscopic surgery (CLS) for sigmoid and rectal cancer at our hospital between January 2018 and December 2018. The study aimed to compare the general characteristics, perioperative indicators, postoperative complications, and five-year follow-up results between the two groups.

Results

A total of 121 eligible patients were enrolled, with 52 underwent laparoscopic-assisted transanal NOSE and 69 underwent CLS. There were no significant differences observed between the two groups in terms of gender, age, body mass index (BMI), TNM stage, etc. (P > 0.05). However, the NOSE group exhibited significantly shorter total incision length and longer operation time compared to the CLS group (P < 0.05). There were no statistically significant differences observed between the two groups in terms of positive rate of bacterial culture, incidence rates of intraabdominal infections or anastomotic leakage (P > 0.05). Furthermore, during follow-up period there was no statistically significant difference observed between these two groups concerning overall survival rate and disease-free survival outcomes (P > 0.05).

Conclusions

The management of surgical complications in CLS is exemplary, with NOSE presenting a sole advantage in terms of incision length albeit at the cost of prolonged operative time. Therefore, NOSE may be deemed appropriate for patients who place high emphasis on postoperative cosmetic outcomes.

[Diagnosis and treatment of malignant mesothelioma of the tunica vaginalis testis: a series of 7 cases]

Objective: To investigate the clinical features, diagnosis, prognosis of malignant mesothelioma of the tunica vaginalis testis (MMTVT). Methods: The clinicopathological data of 7 patients with MMTVT who treated at Sun Yat-sen University Cancer Center between January 2010 and October 2022 were retrospectively reviewed. Cases were first diagnosed at (M (IQR)) 49 (23) years old (range: 27 to 64 years old). The main clinical manifestations were scrotal enlargement (7 cases) and hydrocele (2 cases). Results: Three patients underwent radical orchiectomy as initial treatment, 2 cases underwent hydrocelectomy due to diagnosis of hydrocele, followed by radical orchiectomy at Sun Yat-sen University Cancer Center, and 2 cases underwent transscrotal orchiectomy. Common tumor markers of testicular cancer were not significantly elevated in MMTVT. The expression of tumor PD-L1 was positive in 2 out of the 3 cases. One patient received adjuvant chemotherapy and 2 patients received first-line chemotherapy after tumor recurrence. Chemotherapy regimens used include cisplatin+pemetrexed. Up to October 2022, 3 cases relapsed, of which 2 cases died. The median overall survival was 35 months (range: 4 to 87 months) and the median progression-free survival was 6 months (range: 2 to 87 months). Conclusions: MMTVT at early stage should be treated with early radical orchiectomy and followed up closely after surgery. The cisplatin+pemetrexed regimen is a common option for the treatment of metastatic MMTVT, while whether immune checkpoint inhibitors could serve as a second-line treatment option deserves further research.

Local resection versus radical resection after neoadjuvant chemoradiotherapy for patients with locally advanced rectal cancer: a propensity-score matched cohort analysis

BACKGROUND

We aimed to address the shortage of evidence regarding the safety of the local resection approach by comparing long-term oncological outcomes between patients managed by local resection and those who underwent radical resection.

METHODS

This was a propensity-score matched cohort analysis study that included patients of all ages diagnosed with locally advanced rectal cancer (LARC) who had received neoadjuvant chemoradiotherapy (nCRT) at the Fujian Medical University Union Hospital and Fujian Medical University Affiliated Zhangzhou Hospital, China, between Jan 10, 2011, to Dec 28, 2021. Partial patients with a significant downstage of the tumor were offered management with the local resection approach, and most of the rest were offered radical resection if eligible.

FINDINGS

One thousand six hundred ninety-three patients underwent radical resection after nCRT, and another 60 patients performed local resection. The median follow-up times were 44.0 months (interquartile range = 4-107 months). After propensity-core matching (PSM), in the Kaplan-Meier curves, local resection (n = 56) or radical resection (n = 211) was not significantly associated with 1-, 3-, and 5-year cumulative incidence of overall survival (OS) (HR = 1.103, 95% CI: 0.372 ~ 3.266), disease-free survival (DFS) ((HR = 0.972, 95% CI: 0.401 ~ 2.359), local recurrence (HR = 1.044, 95% CI: 0.225 ~ 4.847), and distant metastasis (HR = 0.818, 95% CI: 0.280 ~ 2.387) (all log-rank P > 0.05). Similarly, multivariate Cox regression analysis indicates that local excision still was not an independent risk factor for OS (HR = 0.863, 95% CI: 0.267 ~ 2.785, P = 0.805) and DFS (HR = 0.885, 95% CI: 0.353 ~ 2.215, p = 0.794).

CONCLUSION

Local resection can be a management option in selected patients with middle-low rectal cancer after nCRT for LARC and without loss of oncological safety at five years.

[A clinicopathological classification of space-occupying lesions of the orbit in 1 913 patients from 2000 to 2021]

Objective: To investigate the histopathological classification of orbital space-occupying lesions. Methods: This is a retrospective case series study. The clinical and pathological data of 1 913 tissue specimens from 1 913 patients with space-occupying lesions of the orbit which were examined in the Second Affiliated Hospital, Zhejiang University School of Medicine from January 2000 to December 2021 were collected. The mass lesions were classified based on histogenesis, pathological nature and age. Results: There were 913 males (47.7%) and 1 000 females (52.3%). The lesions were benign in 1 489 patients (77.8%) and malignant in 424 patients (22.2%). Based on histogenesis, there were 521 vasculogenic lesions (27.2%), which rancked first, 407 cystoid lesions (21.3%), 277 lymphoproliferative lesions (14.5%), 182 lacrimal gland lesions (9.5%) and 121 inflammatory lesions (6.3%). By pathological nature, there were 1 489 benign lesions, including cavernous hemangioma (275, 14.4%), dermoid cyst (225, 11.8%), other hemangiomas (199, 10.4%), epidermoid cyst (136, 7.1%) and benign mixed tumor of the lacrimal gland (134, 7.0%), and 257 malignant lesions, including lymphoma (210, 11.0%) and sebaceous gland carcinoma (47, 2.5%). The age of all patients ranged from 0 to 90 years, while 247 lesions (12.9%) occurred in patients aged 0 to18 years, 1 270 lesions (66.4%) in patients aged 19 to 59 years, and 396 lesions (20.7%) in patients aged 60 to 90 years. Conclusions: In 22 years, almost 2/3 benign orbital lesions in the Second Affiliated Hospital, Zhejiang University School of Medicine occurred in young and middle-aged patients, and males were fewer than females. The most common benign orbital tumors was cavernous hemangioma, followed by dermoid cyst and epidermoid cyst. And the most common malignant orbital tumor was lymphoma, which occurred more frequently in older patients.

Response of sugar metabolism in the cotyledons and roots of Ricinus communis subjected to salt stress

Ricinus communis is an important oilseed crop worldwide and is also considered one of the best potential plants for salt-affected soil improvement in northeast China. However, little is known about photosynthesis and carbohydrate metabolism in this plant, nor the distribution of carbohydrates in cotyledons and roots under salinity stress. In the present study, seedling growth, gas exchange parameters (P_N , E, g_s and C_i ), carbohydrate (fructose, sucrose, glucose, soluble sugar and starch) metabolism and related enzymes and genes were measured in Ricinus plants. Under salt stress, P_N of cotyledons decreased significantly (P < 0.05), resulting in weak photosynthetic capacity. Furthermore, salt stress increased sucrose and glucose content in cotyledons, but decreased soluble sugar and starch content. However, sucrose increased and starch decreased in roots. This may be correlated with the increasing sugar metabolism under salinity, including notable changes in sugar-related enzyme activities (SPS, SuSy, α-amylase and β-amylase) and gene expression of RcINV, RcSUS, RcAmY, RcBAM and RcGBE1. The results suggest that salinity reduces photosynthesis of cotyledons, alters carbohydrate allocation between cotyledons and roots and also promotes starch utilization in cotyledons and starch biosynthesis in roots, leading to a functional imbalance between cotyledons and roots. Together, these findings provide insights into the crucial role of sugar metabolism in improving salt-tolerance of Ricinus during the early seedling growth stage.

[Efficacy and safety of neoadjuvant toripalimab combined with nimotuzumab and chemotherapy in patients with unresectable stage Ⅳ squamous cell carcinoma of penis]

Objective: To compare the efficacy and safety of neoadjuvant chemotherapy alone or combined with toripalimab and nimotuzumab in patients with unresectable locally advanced or metastatic squamous cell carcinoma of penis. Methods: A total of 33 patients with unresectable squamous cell carcinoma of penis undergoing neoadjuvant chemotherapy alone or combined with toripalimab and nimotuzumab at Sun Yat-sen University Cancer Center from May 2015 to June 2021 were enrolled retrospectively. All the patients were male, with a median age (M(IQR))of 49.0 (13.5) years (range: 30 to 70 years). According to the therapy protocols, patients were divided into the chemotherapy group (16 cases) and the triple combination group (17 cases). Log-rank test was used to compare the progression-free survival and overall survival. χ² test or Fisher exact method was used to compare the objective response rate, pathological down-stage rate and adverse events between these two groups. Results: The follow-up time was 28.1(19.2) months (range: 1.5 to 33.4 months). Patients of triple combination group were observed significantly longer progression-free survival (30.0 months vs. 8.2 months, χ²=3.998, P=0.046) than those of chemotherapy group. The median overall survival of the triple combination group and chemotherapy group were not reached and 15.2 months (χ²=3.298, P=0.069), respectively. Although there was no significant difference in the subsequent surgical resection rate between these two groups (12/17 vs.11/16, P=1), the objective response rate and the pathological complete response rate in triple combination group were significantly higher than in chemotherapy group (13/17 vs. 6/16, χ²=5.125, P=0.024; 6/7 vs. 0, P=0.001). The main common grade 1 to 2 adverse events in the triple combination group were alopecia (16 cases), anemia (15 cases), and nausea (14 cases). The main common grade 1 to 2 adverse events in the chemotherapy group were anemia (14 cases), alopecia (12 cases), decreased appetite (12 cases), and nausea (11 cases). The incidence of adverse events ≥grade 3 was similar in the triple combination group and chemotherapy group (8/17 vs. 6/16, χ²=0.308, P=0.579). There was no grade 3 adverse event in both groups. Conclusion: Compared with traditional chemotherapy alone, chemotherapy combined with toripalimab and nimotuzumab provides longer progression-free survival and similar toxicity for unresectable stage Ⅳ squamous cell carcinoma of penis.

[Clinicopathological characteristics of H3K27-altered diffuse midline glioma and evaluation of NTRK as its therapeutic target]

Objective: To investigate the clinicopathological characteristics of H3K27-altered diffuse midline glioma (DMG), and to analyze DMG's prognostic factors, and subsequently, to study the possibility of using NTRK as a therapeutic target for DMG. Methods: A total of 232 DMG diagnosed at the Sanbo Brain Hospital, Capital Medical University, Beijing, China from July 2016 to March 2021 were collected. Their clinical, radiological and pathological features, the ratio of MGMT promoter methylation, expression of NTRK, and characteristics of NTRK gene fusion were analyzed. The prognostic values of different factors were also studied, including age, tumor location, histological grade, gene and protein expression of NTRK, and postoperative adjuvant therapy. Results: Among the 232 DMG cases, there were 8 patients with both primary and relapse tumors on the record. Thus, a total of 224 patients were analyzed, including 118 males and 106 females. There were 126 adults (>18 years of age) and 98 children (≤18 years of age). Notably, the most frequent location was thalamus (41/126, 32.5%) in adults, but brainstem (59/96, 60.2%) in children. The lesions showed T1 hypointensity or isointensity, and T2 hyperintensity. However, contrast enhancement patterns of the tumors varied, with many tumors lacking contrast-enhancing. The histological grades included grade 2 (9/224, 4.0%), grade 3 (41/224, 18.3%) and grade 4 (174/224, 77.7%). Two hundred and twenty-four DMGs were diffusely positive for H3K27M and negative for H3K27me3. The ratio of MGMT promoter methylation was low (1/45, 2.2%). One hundred and seventy-seven of the 224 cases (177/224, 79.0%) were positive for NTRK. Fifty cases were analyzed using fluorescence in situ hybridization. Among them, five DMGs (positive rate, 10.0%) were NTRK fusion positive. This study showed that there were no differences between adult and pediatric DMGs in histological grading, expression of NTRK, and NTRK gene fusion. One hundred and fifty-nine patients were included in the follow-up analysis (P>0.05). During the follow-up period, 109/159 patients (69.6%) died of the disease, with a median survival time of 12 months (range 1 to 55 months). Univariate log-rank analysis showed that age, location, surgical procedure and postoperative adjuvant therapy were associated with overall survivals of the DMG patients (P<0.05). Conclusions: The prognosis of DMG is poor overall. There are differences between adult and pediatric DMGs in anatomic location and prognosis, but not in other features. NTRK1 gene fusion is detected in 10.0% of the tumors. It suggests that TRK inhibitor might be a choice for treating DMG.

[Advances of nanomaterials applied in ophthalmic treatment]

Nanomaterials have been used in many aspects of ophthalmic treatment. By emphasizing the ubiquitous characteristics of nanoparticles and composites, we first explained their relatively mature applications in drug delivery. Then we reviewed the research on nanomaterials in regenerative medicine and gene therapy in recent years. We also discussed the main limitations of the wider application of nanomaterials in ophthalmology: stability, biotoxicity and preclinical-clinical differences. The development of efficient and non-toxic nanomaterials, combined with appropriate transportation systems and application occasions, will provide more possibilities for the future application of nanomaterials in ophthalmic treatments.

A scintillator attenuation spectrometer for intense gamma-rays

A new type of compact high-resolution high-sensitivity gamma-ray spectrometer for short-pulse intense gamma-rays (250 keV to 50 MeV) has been developed by combining the principles of scintillators and attenuation spectrometers. The first prototype of this scintillator attenuation spectrometer (SAS) was tested successfully in Trident laser experiments at LANL. Later versions have been used extensively in the Texas Petawatt laser experiments in Austin, TX, and more recently in OMEGA-EP laser experiments at LLE, Rochester, NY. The SAS is particularly useful for high-repetition-rate laser applications. Here, we give a concise description of the design principles, capabilities, and sample preliminary results of the SAS.

[Preliminary efficacy of ab interno canaloplasty combined with micro-incision cataract surgery in primary open angle glaucoma combined with cataract: one-year results]

Objective: To evaluate the preliminary efficacy and safety of ab interno canaloplasty (ABiC) combined with micro-incision cataract surgery for treating primary open angle glaucoma (POAG) combined with cataract. Methods: Prospective case series study. Patients diagnosed with POAG and concurrent cataract were enrolled to receive ABiC combined with micro-incision phacoemulsification and intraocular lens implantation in the Eye Center of the Second Affiliated Hospital of Zhejiang University School of Medicine from June 2018 to October 2019. Intraocular pressure (IOP), use of hypotensive medications, visual acuity, visual field, and optic nerve at baseline as well as at 1 day, 1 week, 1 month, 3 months, 6 months, and 12 months postoperatively were assessed. Subgroup analyses were further performed to evaluate these data between controlled and uncontrolled POAG, as well as among mild, moderate, and advanced POAG. Success rate and complications were analyzed. Results: A total of 68 eyes in 42 patients completed a follow-up of 12 months. Compared to the baseline IOP under medical control [(18.25±2.65) mmHg (1 mmHg=0.133 kPa)], the mean postoperative IOP at 1 month [(14.31±3.25) mmHg], 3 months [(14.00±3.09) mmHg], 6 months[ (14.58±2.93) mmHg], and 12 months[ (14.84±2.73) mmHg] was all significantly reduced (P<0.05). The median (upper quadrant, lower quadrant) of the hypotensive medication number was 2.5 (2, 3) at baseline, which was significantly reduced to 0 (0, 1) at 1 month, and 0 (0, 0) at 3, 6, and 12 months (P<0.05). The complete success rate and qualified success rate at 12 months were 80.88%(55/68) and 89.71%(61/68), respectively. No deterioration in the visual field or optical coherence tomography scan of the optic nerve was observed at 12 months compared to the baseline status. Hyphema (26 eyes, 38.24%) and transient IOP spike (23 eyes, 33.82%) were the most common complications, but no severe case was present. Conclusion: ABiC combined with micro-incision cataract surgery is considerably effective and safe in the treatment of POAG combined with cataract in the Chinese population.

[Pediatric SMARCB1/INI1-deficient poorly differentiated chordoma of the skull base: report of five cases and review of literature]

Objective: To investigate the clinicopathological characteristics and differential diagnosis of pediatric SMARCB1/INI1-deficient poorly differentiated chordoma (PDC) of the skull base. Methods: Five cases of SMARCB1/INI1-deficient PDC were identified in 139 cases of chordoma diagnosed in Sanbo Brain Institute, Capital Medical University, Beijing, China from March 2017 to March 2021. The clinical and imaging data of the 5 PDCs were collected. H&E and immunohistochemical staining, and DNA methylation array were used, and the relevant literatures were reviewed. Results: All 5 PDCs were located at the clivus. The average age of the patients was 6.4 years, ranging from 3 to 16 years. Three patients were female and two were male. Morphologically, in contrast with classical chordomas, they presented as epithelioid or spindle tumor cells organized in sheets or nests, with necrosis, active mitoses, and infiltration into surrounding tissue. All cases showed positivity of CKpan, EMA, vimentin and brachyury (nuclear stain), and loss of nuclear SMARCB1/INI1 expression. S-100 protein expression was not frequent (2/5). Ki-67 proliferative index was high (20%-50%). All cases had over-expressed p53. It was necessary to differentiate SMARCB1/INI1-dificient PDC from SMARCB1/INI1-dificient tumors occurring at skull base of children or the tumors with epithelial and spindle cell morphological features. The 3 PDCs with DNA methylation testing showed the methylation profiles different from the pediatric atypical teratoid/rhabdoid tumors. They formed an independent methylation profile cluster. The clinical prognosis of the 5 patients was poor, and the overall survival time was 2-17 months. Conclusions: PDC is a special subtype of chordoma, which often affects children and occurs in the clivus. The PDC shares epithelioid or spindle cell morphologic features which are different from the classic chordoma. Besides the typical immunohistochemical profile of chordoma, PDC also has loss of nuclear SMARCB1/INI1 expression and distinct epigenetic characteristics.

Chemical crystallography by serial femtosecond X-ray diffraction

Inorganic-organic hybrid materials represent a large share of newly reported structures, owing to their simple synthetic routes and customizable properties1. This proliferation has led to a characterization bottleneck: many hybrid materials are obligate microcrystals with low symmetry and severe radiation sensitivity, interfering with the standard techniques of single-crystal X-ray diffraction2,3 and electron microdiffraction4-11. Here we demonstrate small-molecule serial femtosecond X-ray crystallography (smSFX) for the determination of material crystal structures from microcrystals. We subjected microcrystalline suspensions to X-ray free-electron laser radiation12,13 and obtained thousands of randomly oriented diffraction patterns. We determined unit cells by aggregating spot-finding results into high-resolution powder diffractograms. After indexing the sparse serial patterns by a graph theory approach14, the resulting datasets can be solved and refined using standard tools for single-crystal diffraction data15-17. We describe the ab initio structure solutions of mithrene (AgSePh)18-20, thiorene (AgSPh) and tethrene (AgTePh), of which the latter two were previously unknown structures. In thiorene, we identify a geometric change in the silver-silver bonding network that is linked to its divergent optoelectronic properties20. We demonstrate that smSFX can be applied as a general technique for structure determination of beam-sensitive microcrystalline materials at near-ambient temperature and pressure.

Dapagliflozin decreases atherosclerotic plaque instability via regulating macrophage pyroptosis

Background

Vulnerable plaques are characterized by infiltration of inflammatory cells, playing a key role in the progression of acute coronary events. It's important to clarify the inflammatory mechanism of unstable plaque formation. Several clinical trials have demonstrated that dapagliflozin could reduce major adverse cardiac events in whether diabetic or non-diabetic patients. However, the underlying cardioprotective mechanism of dapagliflozin remains unclear. This study was aimed to investigate the role of dapagliflozin in regulating macrophage pyroptosis and vulnerable plaque formation.

Methods

20 ApoE−/− mice (control) were fed with high fat diet while another 20 ApoE−/− mice were challenged with high fat diet plus dapagliflozin for 12 weeks. The extent and instability of atherosclerotic plaque was determined by oil-red staining, HE staining, immunofluorescence staining and electron microscopy. Changes in subsets of immune cells were evaluated by flow cytometry. Plasma cytokines were assessed by ELISA. Microarray analysis was applied to detect gene expressions while Western blot and real-time PCR was used to assess gene expression levels.

Results

Morphology studies revealed that dapagliflozin could inhibit plaque formation and reduce instability in ApoE−/− mice. FACS data showed that dapagliflozin could decrease CD11b+Ly6Chigh M1 macrophages differentiation and inhibit foam cells formation in ApoE−/− mice. Microarray analysis and in vitro studies exhibited that dapagliflozin could induce the down regulation of NLRP3, caspase-1, IL-1β, IL-18 and MMP-7/10/12/14 to retard macrophage pyroptosis and foam cell formation.

Conclusions

We have characterized a novel role for dapagliflozin in modulating atherosclerotic lesion development and progression. We envision that this study may provide several potential therapeutic targets for treatment of acute coronary syndromes.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Shanghai Sailing Program

Nanoscale lattice dynamics in hexagonal boron nitride moiré superlattices

Twisted two-dimensional van der Waals (vdW) heterostructures have unlocked a new means for manipulating the properties of quantum materials. The resulting mesoscopic moiré superlattices are accessible to a wide variety of scanning probes. To date, spatially-resolved techniques have prioritized electronic structure visualization, with lattice response experiments only in their infancy. Here, we therefore investigate lattice dynamics in twisted layers of hexagonal boron nitride (hBN), formed by a minute twist angle between two hBN monolayers assembled on a graphite substrate. Nano-infrared (nano-IR) spectroscopy reveals systematic variations of the in-plane optical phonon frequencies amongst the triangular domains and domain walls in the hBN moiré superlattices. Our first-principles calculations unveil a local and stacking-dependent interaction with the underlying graphite, prompting symmetry-breaking between the otherwise identical neighboring moiré domains of twisted hBN.

Here, the authors investigate the lattice dynamics of twisted hexagonal boron nitride layers via nano-infrared spectroscopy, showing local and stacking-dependent variations of the optical phonon frequencies associated to the interaction with the graphite substrate.

[Emphasizing the critical issues in perioperative management of children with congenital cataract]

Cataract is the main cause of treatable visual impairment in children. Children face more risks during the perioperative period of cataract surgery than adults because of their anatomical, physiological, behavioral, and developmental characteristics; therefore, special attention and management are required. This article comprehensively discusses the perioperative management of children's cataract surgery on the base of relevant literatures and the authors' clinical experience, including the indications and timing of surgery, preoperative examination, prevention and treatment of surgical complications, and postoperative visual function reconstruction. (Chin J Ophthalmol, 2021, 57: 481-486).

Strongly Quantum-Confined Blue-Emitting Excitons in Chemically Configurable Multiquantum Wells

Light matter interactions are greatly enhanced in two-dimensional (2D) semiconductors because of strong excitonic effects. Many optoelectronic applications would benefit from creating stacks of atomically thin 2D semiconductors separated by insulating barrier layers, forming multiquantum-well structures. However, most 2D transition metal chalcogenide systems require serial stacking to create van der Waals multilayers. Hybrid metal organic chalcogenolates (MOChas) are self-assembling hybrid materials that combine multiquantum-well properties with scalable chemical synthesis and air stability. In this work, we use spatially resolved linear and nonlinear optical spectroscopies over a range of temperatures to study the strongly excitonic optical properties of mithrene, that is, silver benzeneselenolate, and its synthetic isostructures. We experimentally probe s-type bright excitons and p-type excitonic dark states formed in the quantum confined 2D inorganic monolayers of silver selenide with exciton binding energy up to ∼0.4 eV, matching recent theoretical predictions of the material class. We further show that mithrene's highly efficient blue photoluminescence, ultrafast exciton radiative dynamics, as well as flexible tunability of molecular structure and optical properties demonstrate great potential of MOChas for constructing optoelectronic and quantum excitonic devices.

Enhanced tunable second harmonic generation from twistable interfaces and vertical superlattices in boron nitride homostructures

Broken symmetries induce strong even-order nonlinear optical responses in materials and at interfaces. Unlike conventional covalently bonded nonlinear crystals, van der Waals (vdW) heterostructures feature layers that can be stacked at arbitrary angles, giving complete control over the presence or lack of inversion symmetry at a crystal interface. Here, we report highly tunable second harmonic generation (SHG) from nanomechanically rotatable stacks of bulk hexagonal boron nitride (BN) crystals and introduce the term twistoptics to describe studies of optical properties in twistable vdW systems. By suppressing residual bulk effects, we observe SHG intensity modulated by a factor of more than 50, and polarization patterns determined by moiré interface symmetry. Last, we demonstrate greatly enhanced conversion efficiency in vdW vertical superlattice structures with multiple symmetry-broken interfaces. Our study paves the way for compact twistoptics architectures aimed at efficient tunable frequency conversion and demonstrates SHG as a robust probe of buried vdW interfaces.

Damage-Free Atomic Layer Etch of WSe2: A Platform for Fabricating Clean Two-Dimensional Devices

The development of a controllable, selective, and repeatable etch process is crucial for controlling the layer thickness and patterning of two-dimensional (2D) materials. However, the atomically thin dimensions and high structural similarity of different 2D materials make it difficult to adapt conventional thin-film etch processes. In this work, we propose a selective, damage-free atomic layer etch (ALE) that enables layer-by-layer removal of monolayer WSe₂ without altering the physical, optical, and electronic properties of the underlying layers. The etch uses a top-down approach where the topmost layer is oxidized in a self-limited manner and then removed using a selective etch. Using a comprehensive set of material, optical, and electrical characterization, we show that the quality of our ALE processed layers is comparable to that of pristine layers of similar thickness. The ALE processed WSe₂ layers preserve their bright photoluminescence characteristics and possess high room-temperature hole mobilities of 515 cm²/V·s, essential for fabricating high-performance 2D devices. Further, using graphene as a testbed, we demonstrate the fabrication of ultra-clean 2D devices using a sacrificial monolayer WSe₂ layer to protect the channel during processing, which is etched in the final process step in a technique we call sacrificial WSe₂ with ALE processing (SWAP). The graphene transistors made using the SWAP technique demonstrate high room-temperature field-effect mobilities, up to 200,000 cm²/V·s, better than previously reported unencapsulated graphene devices.

Anisotropic 2D excitons unveiled in organic-inorganic quantum wells

Two-dimensional (2D) excitons arise from electron-hole confinement along one spatial dimension. Such excitations are often described in terms of Frenkel or Wannier limits according to the degree of exciton spatial localization and the surrounding dielectric environment. In hybrid material systems, such as the 2D perovskites, the complex underlying interactions lead to excitons of an intermediate nature, whose description lies somewhere between the two limits, and a better physical description is needed. Here, we explore the photophysics of a tuneable materials platform where covalently bonded metal-chalcogenide layers are spaced by organic ligands that provide confinement barriers for charge carriers in the inorganic layer. We consider self-assembled, layered bulk silver benzeneselenolate, [AgSePh]_∞, and use a combination of transient absorption spectroscopy and ab initio GW plus Bethe-Salpeter equation calculations. We demonstrate that in this non-polar dielectric environment, strongly anisotropic excitons dominate the optical transitions of [AgSePh]_∞. We find that the transient absorption measurements at room temperature can be understood in terms of low-lying excitons confined to the AgSe planes with in-plane anisotropy, featuring anisotropic absorption and emission. Finally, we present a pathway to control the exciton behaviour by changing the chalcogen in the material lattice. Our studies unveil unexpected excitonic anisotropies in an unexplored class of tuneable, yet air-stable, hybrid quantum wells, offering design principles for the engineering of an ordered, yet complex dielectric environment and its effect on the excitonic phenomena in such emerging materials.

Giant nonlinear optical responses from photon-avalanching nanoparticles

Avalanche phenomena use steeply nonlinear dynamics to generate disproportionately large responses from small perturbations, and are found in a multitude of events and materials¹. Photon avalanching enables technologies such as optical phase-conjugate imaging², infrared quantum counting³ and efficient upconverted lasing^4-6. However, the photon-avalanching mechanism underlying these optical applications has been observed only in bulk materials and aggregates^6,7, limiting its utility and impact. Here we report the realization of photon avalanching at room temperature in single nanostructures-small, Tm³⁺-doped upconverting nanocrystals-and demonstrate their use in super-resolution imaging in near-infrared spectral windows of maximal biological transparency. Avalanching nanoparticles (ANPs) can be pumped by continuous-wave lasers, and exhibit all of the defining features of photon avalanching, including clear excitation-power thresholds, exceptionally long rise time at threshold, and a dominant excited-state absorption that is more than 10,000 times larger than ground-state absorption. Beyond the avalanching threshold, ANP emission scales nonlinearly with the 26th power of the pump intensity, owing to induced positive optical feedback in each nanocrystal. This enables the experimental realization of photon-avalanche single-beam super-resolution imaging⁷ with sub-70-nanometre spatial resolution, achieved by using only simple scanning confocal microscopy and without any computational analysis. Pairing their steep nonlinearity with existing super-resolution techniques and computational methods^8-10, ANPs enable imaging with higher resolution and at excitation intensities about 100 times lower than other probes. The low photon-avalanching threshold and excellent photostability of ANPs also suggest their utility in a diverse array of applications, including sub-wavelength imaging^7,11,12 and optical and environmental sensing^13-15.

[Consideration and prevention of the aerosol transmission of 2019 novel coronavirus]

This article was published ahead of print on the official website of Chinese Journal of Ophthalmology on March 14, 2020. Novel coronavirus pneumonia broke out and spread to the whole nation since December 2019. The fight against the virus is now at a critical stage. Previous epidemiological investigations and animal experiments suggested aerosol could perform as a virus transmitter. Based on the clinical observation, the possibility of aerosol transmission of 2019 novel coronavirus has aroused much attention. This article focuses on the feature of aerosol transmission and the pathogens involved in. We analyze the possibility of aerosol transmission of the novel coronavirus. Relevant strategies for preventing novel coronavirus pneumonia are established for the medical personnel and general public during their work or daily life. (Chin J Ophthalmol, 2020, 56:653-656).

[Emphasizing the prevention and management of dry eye during the perioperative period of cataract surgery]

Dry eye is a common ocular surface disease that can occur in more than half of cataract patients before surgery. The perioperative damage to ocular surface can lead to tear film insufficiency and a series of dry eye symptoms, which reduce the visual outcome and life quality of the patients. Therefore, clinicians should standardize the management of dry eye disease during the perioperative period of cataract surgery to further improve patients' satisfaction with surgery, in terms of the evaluation and optimization of preoperative ocular surface, the protection of ocular surface during surgery, and the diagnosis and treatment of postoperative dry eye disease. ( Chin J Ophthalmol, 2020, 56: 409-413).

[A summary of 70 years of cataract diagnosis and treatment in China]

Since the founding of the People's Republic of China, with the unremitting efforts of several generations of ophthalmologists, the level of cataract diagnosis and treatment in our country has made great progress, which has made a significant contribution to the cause of preventing and treating blindness. On the occasion of the 70th anniversary of Chinese Journal of Ophthalmology, this article reviews the development of cataract surgery and intraocular lenses, aiming to help better understand the key points and breakthroughs in cataract diagnosis and treatment in our country at various historical periods, and to encourage the new generation of ophthalmologists to work hard to further promote the progress of ophthalmology in China. (Chin J Ophthalmol, 2020, 56: 321-324).

Controlled Assembly of Upconverting Nanoparticles for Low-Threshold Microlasers and Their Imaging in Scattering Media

Micron-sized lasers fabricated from upconverting nanoparticles (UCNP) coupled to whispering gallery mode (WGM) microresonators can exhibit continuous-wave anti-Stokes lasing useful for tracking cells, environmental sensing, and coherent stimulation of biological activity. The integration of these microlasers into organisms and microelectronics requires even smaller diameters, however, which raises threshold pump powers beyond practical limits for biological applications. To meet the need for low lasing thresholds and high fidelity fabrication methods, we use correlative optical and electron microscopy to uncover the nanoparticle assembly process and structural factors that determine efficient upconverted lasing. We show that 5 μm microspheres with controlled submonolayer UCNP coatings exhibit, on average, 25-fold lower laser thresholds (1.7 ± 0.7 kW/cm²) compared to the mean values of the lowest threshold UCNP lasers, and variability is reduced 30-fold. WGMs are observed in the upconversion spectra for TiO₂-coated microspheres as small as 3 μm, a size at which optical losses had previously prevented such observations. Finally, we demonstrate that the WGM signatures of these upconverting microlasers can be imaged and distinguished through tissue-mimicking phantoms. These advances will enable the fabrication of more efficient upconverting lasers for imaging, sensing, and actuation in optically complex environments.

Continuous Wave Sum Frequency Generation and Imaging of Monolayer and Heterobilayer Two-Dimensional Semiconductors

We report continuous-wave second harmonic and sum frequency generation from two-dimensional transition metal dichalcogenide monolayers and their heterostructures with pump irradiances several orders of magnitude lower than those of conventional pulsed experiments. The high nonlinear efficiency originates from above-gap excitons in the band nesting regions, as revealed by wavelength-dependent second order optical susceptibilities quantified in four common monolayer transition metal dichalcogenides. Using sum frequency excitation spectroscopy and imaging, we identify and distinguish one- and two-photon resonances in both monolayers and heterobilayers. Data for heterostructures reveal responses from constituent layers accompanied by nonlinear signal correlated with interlayer transitions. We demonstrate spatial mapping of heterogeneous interlayer coupling by sum frequency and second harmonic confocal microscopy on heterobilayer MoSe₂/WSe₂.

[A clinicopathological classification analysis of ocular mass lesions in 7 910 cases]

Objective: To investigate the anatomical region, histopathological classification and histogensis distribution of ocular mass lesions in South China. Methods: Retrospective cases study. The clinical and pathological data of 7 910 samples with ocular (adnexal) tumors or proliferative lesions which were examined from January 2000 to May 2018 were retrospectively retrieved. The constituent ratios of ocular mass lesions in different anatomical regions and histogenesis have been analyzed. Results: There were 3 445 males and 4 465 females aged from 3 months to 106 years. Classification by anatomical region. Eyelid 4 976 cases (62.9%): benign-pigmented nevus (31.7%, 1 342/4 235), squamous cell papilloma (12.3%, 519/4 235), seborrheic keratosis (9.4%, 396/4 235); malignant-basal cell carcinoma (48.5%, 359/741), sebaceous gland carcinoma (34.4%, 255/741), squamous cell carcinoma (12.3%, 91/741). Ocular surface 1 449 cases (18.3%): benign-pigmented nevus (26.6%, 359/1 348), squamous cell papilloma (12.8%, 173/1 348); malignant-lymphoma (34.7%, 35/101), squamous cell carcinoma (30.7%, 31/101).Orbit 1 485 cases (18.8%): benign-hemangioma (28.5%, 332/1 167), lacrimal gland (duct) cyst(13.2%, 154/1 167); malignant-lymphoma (44.7%, 142/318), adenoid cystic carcinoma (10.1%, 32/318). Classification by histogenesis: epithelial 2 145 cases (27.1%), cutaneous appendages 378 cases (4.8%), cystoid 1 068 cases (13.5%), mesenchymal 748 cases (9.5%), lymph-hematopoietic 225 cases (2.8%), neurogenic 31 cases (0.4%), melanocytic 1 765 cases (22.3%), others 1 550 cases (19.6%). Conclusions: Over the past 18 years, the ocular tumors identified at the Second Affiliated Hospital, Zhejiang University School of Medicine most frequently occur in eyelid and originate from epithelium. The most common types are as followings. Benign lesions: pigmented nevus, squamous cell papilloma are the most common types for eyelid and ocular surface, whereas hemangioma, lacrimal gland (duct) cyst and epidermoid cyst are the most common types for orbit. Malignant cancers: basal cell carcinoma is the most prevalent disease in eyelid, whereas lymphoma occurs more frequently in ocular surface and orbit. (Chin J Ophthalmol, 2019, 55: 847-853).

[Emphasizing the overall management of cataract surgery in patients with diabetes]

Cataract is one of the common cause of vision decrease in diabetic patients, which occurs earlier and develops faster than in common patients, and often requires surgery for treatment. However, diabetic patients are more likely to have fundus lesions, and are more prone to have complications, such as infection, posterior capsular opacity, cystoid macular edema, etc. Diabetic patients have a higher risk of cataract surgery than ordinary cataract patients. Therefore, clinicians should be conscious about the particularity of diabetic cataract surgery, develop an appropriate and individual diagnosis and treatment plan according to its characteristics, and regulate the overall management to prevent possible risks and ensure the safety of patients.(Chin J Ophthalmol, 2019, 55: 481-484).

High-sensitivity far-forward collective scattering diagnostic on HL-2A tokamak

The multichannel formic acid (HCOOH, λ = 432.5 µm) laser interferometer and Faraday-effect polarimeter on HL-2A tokamak have been developed to measure the far-forward collective scattering from electron density fluctuations. The far-forward collective scattering system provides eight channels of line-integrated electron density fluctuations, covering the wave-number range: k_⊥ < 1.6 cm^-1. With the new diagnostic, the density fluctuations caused by plasma energetic particles and turbulence have been routinely observed in HL-2A experiments.

[Clinical outcome of postchemotherapy retroperitoneal lymph node dissection and predicting retroperitoneal histology in advanced nonseminomatous germ cell tumours of the testis]

Objective: To explore the clinical outcome of advanced testicular nonseminomatous germ cell cancer patients undergoing post chemotherapy retroperitoneal lymph node dissection (PC-RPLND), and to analyze the relevant prognostic factors of lymph node pathological. Methods: A total of 43 consecutive testicular nonseminomatous germ cell cancer patients underwent PC-RPLND between March 2001 and December 2014 in Department of Urology at Sun Yat-sen University Cancer Center were retrospectively reviewed. The average age of the patients was (29.0±11.5) years (ranging from 12 to 58 years). Before PC-RPLND, 22 patients were classified as phase Ⅱ, while 21 were phase Ⅲ. Primary tumor histology revealed seminomatous elements in 19 cases, embryonal cell carcinoma in 22 cases, yolk sac tumor in 13 cases, chorionic carcinoma in 3 cases, mature teratomatous elements in 11 and immature teratomatous elements in 2 cases. Patients were treated with cisplatin-based chemotherapy after orchectomy and then underwent surgical resection of retroperitoneal lymph nodes.After PC-RPLND, all patients underwent a periodic review including the blood routine, biochemistry routine and computed tomography or ultrasonograph of the chest, the abdomen and the pelvis. The association of pathological data with patient's clinic features and the correlations between molecular features detected with each other were assessed by the t test, χ(2) and Fisher's exact test. Multivariate logistic regression were used to assess prognostic factors. Results: The median operative time was 278 minutes (ranging from 50 to 715 minutes). Median blood loss was 425 ml (ranging from 50 to 5 000 ml). Eight patients received blood transfusion intra-operatively, 2 patients underwent adjunctive surgical procedures, 4 patients developed ileus and 4 had an ascites chylosus following PC-RPLND, 1 patient had a postoperative hyperthermia and retrograde ejaculation was present in 10 patients. The transverse diameter of the residual tumor in patients ranged from 0.8 to 18.2 cm. Necrosis, teratoma and viable germ cell tumors were found in 15, 17 and 11 of all patients. The median follow-up time was 46 months (ranging from 6 to 169 months). There were 39 patients had no tumor recurrence, 7 patients were found recurrence after PC-RPLND, 5 died of malignant germ cell tumor. The normal serum lactate dehydrogenase (LDH) level before chemotherapy (HR=25.811, 95%CI: 0.678 to 982.624, P=0.017) and relative changes more than 50% in retroperitoneal lymph node size (HR=0.016, 95%CI: 0 to 0.698, P=0.032) were statistically significant prognostic factors of the presence of necrosis. Conclusions: Since most residual masses are not sensitive to chemotherapy, PC-RPLND is still an essential part of the treatment of metastatic testicular nonseminomatous germ cell cancer. Patients with the normal serum LDH level before chemotherapy and a shrinkage of 50% or more in retroperitoneal mass have a considerably chance of having necrosis in the retroperitoneum resection. This may help to refine the selection of candidates for PC-RPLND.

Abstract P3-11-04: A model to predict high-risk Oncotype DX scores as defined by the TailorX trial: A report from the National Cancer Data Base

Background: Results from the TailorX clinical trial demonstrated a survival benefit of chemotherapy in those with high-risk (&gt;25) Oncotype DX scores as well as in some patients ≤50yo with intermediate (16-25) scores. The objective of this study was to develop a model that could predict a high-risk Oncotype DX score based on tumor features alone.

Methods: From 2010-2015, 84,549 breast cancer patients with Oncotype DX scores were selected from the National Cancer Data Base. Seven pathologic variables including age, estrogen and progesterone receptor status, histologic subtype, lymphovascular invasion (LVI), grade, and tumor size were used to predict high-risk (&gt;25) Oncotype DX scores using logistic regression. A similar analysis was performed on women ≤50yo to predict low (&lt;15) and intermediate (16-25) scores. Nomograms were created for models using bootstrap estimation method of the model coefficients. Cutoffs with at least 80% positive predictive value (PPV) were chosen to classify patients into high or low-risk Oncotype DX score groups. Accuracy of these predictions were developed in a training set and validated in a testing set.

Results: For patients &gt;50yo, 6,658 (15.1%) of patients had high-risk Oncotype DX scores. The model yielded a moderately strong C-index of 0.80 for Oncotype DX score of &gt;25. For women ≤50yo, 2,044 (13.5%) were high-risk, 5,760 (38.1%) were intermediate-risk and 7,316 (48.4%) were low-risk. The C-index for women ≤50yo was 0.81 for prediction of Oncotype DX score of &gt;25. C-indexes for intermediate and low risk scores were not strong enough to use for prediction (0.54 and 0.67). Estrogen receptor status, progesterone receptor status and grade were the strongest independent predictors of high-risk Oncotype DX scores in women &gt;50yo and ≤50yo. Age was not a good predictor of high-risk scores in women &gt;50yo. When our nomogram was used in the training set, the PPV of a high-risk Oncotype score was 80% with a negative predictive value (NPV) of 87%, sensitivity of 19% and specificity of 99%. In the testing set, PPV was 81%, with a NPV of 87%, sensitivity of 19% and specificity of 99%.

Conclusion: A model incorporating tumor factors can predict a high-risk Oncotype DX score as defined by the recent TailorX trial in all age groups. The model is of limited value in predicting intermediate-risk Oncotype DX scores in women of age ≤50. In resource-constrained healthcare systems, such a model can help identify high risk patients who would benefit from adjuvant chemotherapy without incurring the cost of an Oncotype DX test.

Citation Format: Pesce C, Kuchta K, Wang E, Yao K, El-Tamer M. A model to predict high-risk Oncotype DX scores as defined by the TailorX trial: A report from the National Cancer Data Base [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-11-04.

Abstract P1-09-02: Prevalence of genetic mutations in patients with second primary breast cancers

Background: Women newly diagnosed with primary breast cancer (PBC) often undergo multi-gene panel testing to determine their contralateral breast cancer (BC) risk and whether a contralateral prophylactic mastectomy is warranted. However, with the exception of BRCA1/2, gene-specific associations with contralateral or second PBC (SPBC) have not been established. Methods: The study sample was comprised of 83,278 women with BC referred to a single diagnostic laboratory for multi-gene panel testing. The frequency of pathogenic/likely pathogenic variants in clinically-actionable genes (CAG), including highly penetrant genes (HPG: BRCA1, BRCA2, TP53, PTEN) and moderately penetrant genes (MPG: ATM, CHEK2, PALB2, CDH1, NBN, NF1) was compared between women with a PBC and SPBC. Women with a SPBC &lt;1 year from their first diagnosis were excluded. Logistic regression burden tests were used to test for associations between mutated genes and SPBC adjusting for age at diagnosis of first BC, histology, presence of first- or second-degree relative with BC, and race/ethnicity. Results: The study included 75,550 women with PBC and 7,728 with SPBC. The median (IQR) time between primaries for the SPBC group was 11 (6,17) years . Women with SPBC were slightly more likely to be Caucasian (67.8% vs. 63.4%; p&lt;0.001), older when referred for genetic testing (mean difference 9.7 years, p&lt;0.001), slightly younger at first BC diagnosis (mean difference 2.1 years, p&lt;0.001) and slightly more likely to have &gt;1 first or second degree relative with BC (62.2% vs. 60.8%; p=0.004) than PBC. Among women tested for all CAGs, 4,883 (8.1%) were carriers of pathogenic/likely pathogenic variants (11.1% SPBC vs. 7.8% PBC). CHEK2 was the most frequently mutated gene (3.4% SPBC vs. 2.3% PBC), followed by BRCA1 (2.7% SPBC vs.1.6% PBC), BRCA2 (2.2% SPBC vs. 1.8% PBC), and PALB2 (1.4% SPBC vs. 0.9% PBC). In fully adjusted models, women with SPBC were 1.38 times as likely (p=&lt;0.0001) as women with PBC to test positive for a CAG (OR=1.35 for HPG and 1.34 for MPG). BRCA1 (OR=1.49; p&lt;0.0001), followed by CHEK2 (OR=1.36; p&lt;0.0001) and PALB2 (OR=1.53; p&lt;0.001) were most significantly associated with SPBC. TP53, BARD1, ATM and BRCA2 were marginally associated with SPBC (p=0.01 to 0.06). When results were stratified by race/ethnicity, ORs among Caucasians were similar to those observed overall. Among African Americans, women with SPBC were 1.76 times as likely to carry a CAG (p&lt;0.001) than their PBC counterparts. PALB2 (OR=2.69; p=0.002), BRCA2 (OR=1.85; p=.004), and TP53 (OR=3.88; p=.009) were most significantly associated with SPBC followed by BRCA1 (OR=1.63; p=.002). Analysis of gene associations for other racial/ethnic groups was limited by small sample size. Conclusions: There is a significantly higher prevalence of CAG mutations among women with SPBC, even after adjusting for age at diagnosis and family history. These findings support SPBC as a standalone indication for multigene panel testing. Additional studies aimed to assess cumulative risk of SPBC for CAG beyond BRCA1/2 are needed to help guide clinical management decisions for mutation carriers.

Citation Format: Yao K, Clifford J, Li S, LaDuca H, Hulick PJ, Xu J, Gutierrez S, Black MH. Prevalence of genetic mutations in patients with second primary breast cancers [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-09-02.

Temporal dynamics of the coulomb screening in single layer MoS2

We measure exciton dynamics in single-layer MoS2 with unprecedented temporal resolution and we directly extract the characteristic time-scale for the Coulomb screening dynamics, which ranges between 15 and 35 fs.

Clinical significance of angiopoietin-like protein 3 expression in patients with glioblastoma

There is strong evidence that angiopoietin-like peptide family is involved in the invasiveness and metastasis of cancer. Angiopoietin-like protein 3 (ANGPTL3) is proven to be involved in angiogenesis and tumor development. However, there is no published data on the role ANGPLT3 plays in glioblastomas. The present study was conducted to examine ANGPLT3 proteins expression and its association with clinicopathological factors and prognosis in human glioblastomas. Immunohistochemistry was used to evaluate the expression of ANGPTL3, EGFR and VEGFR. We found that 33 cases (57.9%) that showed strong immunostaining for ANGPTL3 proteins. However, there was no significant difference between the expression of ANGPTL3 and the proangiogenic factors, including EGFR or VEGFR. Patients with high/moderate expression of ANGPTL3 had a significantly shorter survival time (6.3 months) than those (median survival time 13.8 months) with low/negative expression. The overall survival (OS) was also investigated and analyzed by the Kaplan-Meier method, which showed a significant difference (P=0.0045, Breslow test). The present data leads to new insights into the role of ANGPTL3 in glioblastomas and provides an independent predictive factor.

[BRAF V600E mutation and clinicopathologic characteristics in 250 cases of brain tumors associated with epilepsy]

Objective: To investigate the clinicopathologic characteristics and BRAF V600E mutation of brain tumors associated with epilepsy. Methods: Totally 250 patients with brain tumors associated with epilepsy were included from March 2008 to August 2017 retrospectively at Sanbo Brain Hospital, Capital Medical University.The clinical manifestations, histological features and BRAF V600E mutation results were collected and analyzed. Results: There were 132 males and 118 females, and the male to female ratio was 1.1∶1.0. The age of patients ranged from 2 to 67 years(mean 22 years). The tumors had obvious local space occupying effect on MRI. The temporal lobe was the most common site (44.4%, 111/250). There were 58.4% (146/250) of ganglioglioma (GG), 24.0% (60/250) of dysembryoplastic neuroepithelial tumor (DNT), 12.8% (32/250) of pleomorphic xanthoastrocytoma(PXA), 4.0% (10/250) of angiocentric glioma (AG) and 0.8% (2/250) of papillary glioneuronal tumor (PGNT). Mixed GG, PXA and DNT morphological structures were found in 9 of patients. Among 250 cases, 35 cases were accompanied by focal cortical dysplasia(FCD). BRAF V600E was seen in 43 of 74 (58.1%) GG and 13 of 28 (46.4%) PXA. The most common pathologic grade of GG, DNT, AG and PGNT was WHO I. Some of the tumor cells from GG (34 cases) showed higher proliferative activity (WHO Ⅱ/Ⅲ). Most cases of PXA were WHOⅡand high proliferative activity was seen in nine cases. Conclusions: The association of low-grade glioneuronal tumors with intractable epilepsy was well-recognized. The most common low-grade glioneuronal tumors were GG.GG may occur in any part of the central nervous system, with a predilection for temporal lobe. Each type of low-grade glioneuronal tumors has its own unique histological morphology, but some may show complex features with 2 or 3 mixed components. The occurrence of BRAF V600E mutations in GG is common, and their detection may be valuable for the diagnosis and treatment in GG.

Continuous-wave upconverting nanoparticle microlasers

Reducing the size of lasers to microscale dimensions enables new technologies¹ that are specifically tailored for operation in confined spaces ranging from ultra-high-speed microprocessors² to live brain tissue³. However, reduced cavity sizes increase optical losses and require greater input powers to reach lasing thresholds. Multiphoton-pumped lasers^4-7 that have been miniaturized using nanomaterials such as lanthanide-doped upconverting nanoparticles (UCNPs)⁸ as lasing media require high pump intensities to achieve ultraviolet and visible emission and therefore operate under pulsed excitation schemes. Here, we make use of the recently described energy-looping excitation mechanism in Tm³⁺-doped UCNPs⁹ to achieve continuous-wave upconverted lasing action in stand-alone microcavities at excitation fluences as low as 14 kW cm^-2. Continuous-wave lasing is uninterrupted, maximizing signal and enabling modulation of optical interactions¹⁰. By coupling energy-looping nanoparticles to whispering-gallery modes of polystyrene microspheres, we induce stable lasing for more than 5 h at blue and near-infrared wavelengths simultaneously. These microcavities are excited in the biologically transmissive second near-infrared (NIR-II) window and are small enough to be embedded in organisms, tissues or devices. The ability to produce continuous-wave lasing in microcavities immersed in blood serum highlights practical applications of these microscale lasers for sensing and illumination in complex biological environments.

[Safety and efficacy of rotational atherectomy in the interventional treatment of coronary chronic total occlusion lesions]

Objective: To investigate the safety and efficacy of rotational atherectomy in the interventional treatment of coronary chronic total occlusion lesions. Methods: In this retrospective study,a total of 31 consecutive patients with coronary chronic total occlusion(CTO) lesions underwent rotational atherectomy in our hospital from February 2004 to December 2016 were enrolled,and the clinical features were analyzed. Coronary atherectomy was performed if balloon failed to cross the CTO lesions or balloon could not be fully dilated in the CTO lesions after wire crossing. The definition of procedure success was defined as residual stenosis less than 20% after implantation of drug eluting stent and rotational atherectomy. After the procedure, the patients were followed up to observe major adverse cardiac and cerebral vascular events which including cardiogenic death, myocardial infarction, cerebrovascular accident, and target lesion revascularization. Results: The 1.25 mm diameter burr was firstly selected in 80.6% (25/31) patients,and 96.8%(30/31) patients used only 1 burr to complete the rotational atherectomy procedure. The complication rate was 9.8% (3/31) including 1 patient with coronary dissection and 3 patients with slow flow or no flow. There was 1 patent with both coronary dissection and slow flow. The procedure success rate was 96.8%(30/31). Interventional treatment related myocardial infarction occurred in 3 patients during hospitalization.The 30 patients with procedure success were followed up 36(11, 96) months. The incidence rate of major adverse cardiac and cerebral vascular events was 13.3% (4/30), of which the cardiogenic death rate was 3.3% (1/30), the myocardial infarction rate was 6.7% (2/30), cerebrovascular accident rate was 3.3%(1/30),and the target lesion revascularization rate was 6.7% (2/30). Conclusion: Rotational atherectomy is safe and effective in the interventional treatment of coronary CTO lesions.

Prospective multinational serosurveillance study of Bordetella pertussis infection among 10- to 18-year-old Asian children and adolescents

OBJECTIVES

Bordetella pertussis continues to cause outbreaks worldwide. To assess the role of children and adolescent in transmission of pertussis in Asia, we performed a multinational serosurveillance study.

METHODS

From July 2013 to June 2016, individuals aged 10 to 18 years who had not received any pertussis-containing vaccine within the prior year were recruited in 10 centres in Asia. Serum anti-pertussis toxin (PT) IgG was measured by ELISA. Demographic data and medical histories were obtained. In the absence of pertussis immunization, anti-PT IgG ≥62.5 IU/mL was interpreted as B. pertussis infection within 12 months prior, among them levels ≥125 IU/mL were further identified as infection within 6 months.

RESULTS

A total of 1802 individuals were enrolled. Anti-PT IgG geometric mean concentration was 4.5, and 87 (4.8%) individuals had levels ≥62.5 IU/mL; among them, 73 (83.9%) had received three or more doses of pertussis vaccine before age 6 years. Of 30 participants with persistent cough during the past 6 months, one (3.3%) had level ≥125 IU/mL. There was no significant difference in proportions with anti-PT IgG ≥62.5 IU/mL among age groups (13-15 vs. 10-12 years, 16-18 vs. 10-12 years), between types of diphtheria, pertussis and tetanus (DTP; whole cell vs. acellular), number of doses before age 6 years within the DTP whole-cell pertussis vaccine (five vs. four doses) or acellular pertussis vaccine (five vs. four doses) and history of persistent cough during the past 6 months (yes vs. no).

CONCLUSIONS

There is significant circulation of B. pertussis amongst Asian children and adolescents, with one in 20 having serologic evidence of recent infection regardless of vaccination background.

Relationship Cataract Density and Visual Field Damage

In interpreting visual field results, two questions arise: a) what type of visual field damage is produced by cataract, and b) can the influence on the visual field somehow be predicted? To answer these questions, cataract density was quantified with the Opacity Lens Meter (OLM) 701, and visual field tests were done before and after IOL-implantation surgery with Octopus Program G1 in 58 eyes of 58 patients (mean age 71±8 years) with cataract but with no other detectable ocular diseases. The average improvement of mean damage (MD) after surgery was 5.4 dB, and that of D (20) (defect 20 on the Bebie Curve) was 5.7 dB. The improvement of the visual fields was, as expected, statistically highly significant (p<0.0001). The corrected loss variance (CLV), however, increased on the average only by 2.5 dB2, which was not significant. The predictive value of the OLM reading for opacity-induced MD depends on the type of cataract. It is good for cortical and nuclear cataracts but poor for posterior subcapsular opacifications. The overall predictive value (R = 0.66) is, nevertheless, better than for preoperative visual acuity (R = -0.54). If OLM and visual acuity (VA) are considered together, the predictive value is slightly higher (R = 0.72). Thus, optical density influences on visual field performance can be substracted from general visual field results.

[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.

Expression of IFNAR1 and IFNAR2 in cattle placenta during early pregnancy

Interferon-tau (IFNT), a type I interferon, is an antiluteolytic factor secreted by trophoderm during pregnancy. IFNT transmitted signals or stimulated the expression of some factors to build maternal recognition and keep pregnancy by binding its receptors, IFNT receptor 1(IFNAR1) and IFNT receptor 2 (IFNAR2). Up to now, the expression model and roles of IFNAR1 and IFNAR2 in placenta have not been investigated in cattle. In this study, the localization and expression of IFNAR1 and IFNAR2 in the cattle placenta at days 18-50 of pregnancy were detected by histological examination, immunofluorescence staining and real-time qPCR. The results showed that IFNAR1 mainly distributed in chorioallantoic membrane, endometrial epithelium, cotyledon and caruncle during the early pregnancy of cattle with change in time- and position-dependent. IFNAR1 and IFNAR2 mRNA expression were mainly detected in chorioallantoic membrane and cotyledon, and markedly increased along with pregnancy process. Moreover, the mRNA expression level of IFNAR1 in chorioallantoic membrane and cotyledon was higher than that of IFNAR2. IFNAR mRNA was also expressed in caruncle tissues, which experienced a tendency of decrease from days 21 to 36, followed by increase after days 36. These results provide morphological basis and quantitative data for investigating the roles of IFNAR1 and IFNAR2 on development of cattle placenta and pregnancy maintenance.

A high precision flat crystal spectrometer compatible for ultra-high vacuum light source

We report on a flat crystal spectrometer (FCS) featuring a differently pumped rotary feedthrough and double detectors connected to a crystal chamber by extendable bellows built at the Shanghai EBIT Laboratory. It was designed to overcome defects such as oil contamination, little distance from the detector to the crystal and others of an early FCS equipped at the same laboratory, but still keeps a large detectable angle range of detectors and brings new features and functions such as the Bond method measurement and double-crystal measurement which are based on the two-detector and large bellow design. This new FCS could cover an energy range of measurable photons from 570 eV to 10 keV and reach a vacuum better than 6 × 10^-10 Torr and thus is compatible for coupling directly to ultra-high vacuum light sources. Off-line tests of the FCS were undertaken where Kα x-rays from solid titanium were measured and analyzed. Measurements of transitions in He-like argon ions were performed when the spectrometer was directly connected to Shanghai EBIT, and the width of the x-ray source was monitored simultaneously using an x-ray slit imaging system. An observed spectral line broadening was 0.869 eV corresponding to a resolving power of 3600, including Doppler broadening of the x-ray source. Taking account of the measured source width, we made simulations using the SHADOW 3 code and got a nominal resolving power of 6500 for the spectrometer. This high nominal resolving power is due to a longer distance from the crystal to the detector, comparing with that in the early FCS.

[Neuropathologic findings in intractable epilepsy: a clinicopathologic analysis of 822 cases]

Objective: To investigate the clinicopathologic characteristics of intractable epilepsy. Methods: Based on the classification criteria proposed by the International League Against Epilepsy (ILAE), a retrospective analysis of the pathological characteristics was done in 822 patients who underwent epilepsy surgery in Sanbo Brain Hospital, Capital Medical University, from June 2008 to December 2012. Results: The mean age of epilepsy onset was 9.9 years, mean duration of epilepsy was 11.9 years. Complex partial seizures were the main presenting features. Histopathological study showed 33 cases (4.01%) with mild forms of cortical malformations, 690 cases (83.94%) with focal cortical dysplasia (FCD) and 99 cases with others (including 39 pure hippocampal sclerosis, 20 cystosclerosis, 19 Sturge-Weber syndrome, 8 tuberous sclerosis complex, 6 without significant pathological changes, 5 gyral malformations and 2 hamartoma). Among the 690 FCD cases, 106 were FCD typeⅠ, 91 were FCD typeⅡ and 493 were FCDⅢ(Ⅲa: 160, Ⅲb: 106, Ⅲc: 26 and Ⅲd: 201). Conclusions: FCDⅢd is the most common histopathological subtype causing intractable epilepsy, mainly due to focal hypoxia/ischemia in the perinatal period, which results in scarring of local brain tissue; this is followed by other isolated forms of FCD (FCDⅠand FCDⅡ), and then FCD Ⅲa and FCD Ⅲb. The reason to distinguish isolated forms of FCD (types Ⅰ and Ⅱ) from FCD Ⅲ and to subclassify FCD Ⅲ is to allow better definition of cortical dyslamination. Therefore, the pathogenic factors of intractable epilepsy can be grouped in greater details, and facilitate the diagnosis and potential curative treatment of intractable epilepsy.

[A Meta-analysis of comparing effectiveness and safety between minimally invasive video-assisted thyroidectomy and conventional thyroidectomy in the treatment of papillary thyroid carcinoma without lymph node metastasis]

Objective:To compare the effectiveness and safety between minimally invasive video-assisted thyroidectomy (MIVAT) and conventional thyroidectomy (CT) in the treatment of papillary thyroid carcinoma without lymph node metastasis, providing clinicians using video-assisted way to treat thyroid papillary carcinoma with a more reasonable basis.Method:According to the including and excluding criterion,we searched the published articles which compare the effectiveness of MIVAT and CT curing PTC in randomized controlled clinical trials. The searching time was from January 2011 to December 2016, and the data was analyzed by using revman 5.3 software.Result:Twelve articles involving 1 080 cases were included,and there were 514 cases in the MIVAT group and 566 cases in the CT group. The results of metaanalysis showed that: the operation time of MIVAT group is longer than that of CT group (MD=17.19, 95%CI12.43-21.96, P<0.05); however the VAS point of MIVAT group is less than that of CT group in twentyfour hours after surgery (MD-1.07, 95%CI-1.61--0.53, P<0.05). There is no significant difference in the incidences of transient recurrent laryngeal nerve injury(OR=2.21,95%CI0.9-5.07,P>0.05),transient hypoparathyroidism (OR=0.78, 95%CI0.48-1.28, P>0.05), serum thyroglobulin after five years followed up (MD-0.05, 95%CI -0.25-0.16, P>0.05), number of retrieved central lymph nodes (MD=-0.36, 95%CI -0.72-0.01, P>0.05) and number of retrieved central positive lymph nodes (MD=-0.15, 95%CI -0.45-0.16, P>0.05).Conclusion:Using MIVAT treating papillary thyroid carcinoma (without lymph node metastasis) is safe when its indications are strictly controlled.

A Solar-Blind UV Detector Based on Graphene-Microcrystalline Diamond Heterojunctions

An ultraviolet detector is demonstrated through a whole-wafer, thin diamond film transfer process to realize the heterojunction between graphene and microcrystalline diamond (MCD). Conventional direct transfer processes fail to deposit graphene onto the top surface of the MCD film. However, it is found that the 2 µm thick MCD diamond film can be easily peeled off from the growth silicon substrate to expose its smooth backside for the graphene transfer process for high-quality graphene/MCD heterojunctions. A vertical graphene/MCD/metal structure is constructed as the photodiode device using graphene as the transparent top electrode for solar-blind ultraviolet sensing with high responsivity and gain factor. As such, this material system and device architecture could serve as the platform for next-generation optoelectronic systems.