Tight focusing of the vector optical field with polarization varying along complex curves of the Poincaré sphere.

Different from the scalar optical field with spatially uniform polarization, the vector optical field exhibits inhomogeneous distribution of polarization on the cross section. Manipulating the variation of polarization in a single optical beam is important to acquire a flexible and controllable focused optical field. Previous studies mainly focused on the vector optical field with its polarization varying along a circular trajectory of the Poincaré sphere. Here, we demonstrate the tight focusing behaviors of the vector optical field with the polarization varying along complex curves of the Poincaré sphere, which is generated by the joint modulation of azimuthal phase and amplitude distributions of orthogonally polarized components. The longitudinal polarization component with a multipolar pattern in rotational symmetry can be achieved with similar distribution of the total focused field. The transverse and longitudinal spin angular momentum distributions in the focal space are discussed. Approximately pure transverse spin angular momentum can be constructed and manipulated in the focal space, which provides the possibility to manipulate the 3D spin flux for the applications of nano and spin photonics.

Virtual reconstruction of midfacial bone defect based on generative adversarial network.

BACKGROUND: The study aims to evaluate the accuracy of the generative adversarial networks (GAN) for reconstructing bony midfacial defects. METHODS: According to anatomy, the bony midface was divided into five subunit structural regions and artificial defects are manually created on the corresponding CT images. GAN is trained to reconstruct artificial defects to their previous normal shape and tested. The clinical defects are reconstructed by the trained GAN, where the midspan defects were used for qualitative evaluation and the unilateral defects were used for quantitative evaluation. The cosine similarity and the mean error are used to evaluate the accuracy of reconstruction. The Mann-Whitney U test is used to detect whether reconstruction errors were consistent in artificial and unilateral clinical defects. RESULTS: This study included 518 normal CT data, with 415 in training set and 103 in testing set, and 17 real patient data, with 2 midspan defects and 15 unilateral defects. Reconstruction of midspan clinical defects assessed by experts is acceptable. The cosine similarity in the reconstruction of artificial defects and unilateral clinical defects is 0.97 ± 0.01 and 0.96 ± 0.01, P = 0.695. The mean error in the reconstruction of artificial defects and unilateral clinical defects is 0.59 ± 0.31 mm and 0.48 ± 0.08 mm, P = 0.09. CONCLUSION: GAN-based virtual reconstruction technology has reached a high accuracy in testing set, and statistical tests suggest that it can achieve similar results in real patient data. This study has preliminarily solved the problem of bony midfacial defect without reference.

Primary hepatic neuroendocrine tumors: multi-modal imaging features with pathological correlations.

BACKGROUND: Primary hepatic neuroendocrine carcinomas (PHNECs) are rare and asymptomatic, and are therefore difficult to distinguish radiologically from other liver carcinomas. In this study, we aimed to determine the computed tomography (CT), magnetic resonance imaging (MRI), and digital subtraction angiography (DSA) features of PHNECs. METHODS: A retrospective analysis of 11 patients with pathologically proven PHNECs was performed from January 2009 to September 2014. The CT, MRI, and DSA image features were analysed. RESULTS: Ten of the eleven patients exhibited two or more lesions, and one patient exhibited a single lesion. Abdominal CT of 8 cases revealed multiple round or oval-shaped masses with well-defined borders, which were heterogeneous and hypodense on precontrast CT images. Significant diffuse heterogeneous enhancement was observed during the arterial phase in 8 cases, and the enhancement was slightly higher than the attenuation of the surrounding normal liver parenchyma and indistinct edges of small lesions during the portal phase. Well circumscribed (11 cases), lobulated (5 cases) or multiple nodular masses (4 cases), nodule (1 case) and irregular masses (1 case) of high signal intensity were observed on T2WI and DWI of MR images. The masses were well circumscribed, heterogeneous, and hypointense on T1WI, with significant enhancement of the solid carcinoma portion in the early arterial phase and continued enhancement in the portal venous phase. Characteristic lobulated or multiple nodular masses were observed in MRI. DSA showed multiple hypervascular carcinoma-staining lesions with sharp edges in the arterial phase. CONCLUSION: The CT, MRI, and DSA images of PHNECs exhibit specific characteristic features. Appropriate combinations of the available imaging modalities could therefore optimize the evaluation of patients with PHNECs.

[Improving Threshold Segmentation in 3D Reconstruction of Mandible CT Image].

OBJECTIVE: To develop a new threshold segmentation method for mandible image segmentation. METHODS: CT data of 12 volunteers were exported into Mimics 10. 01. An improved method usinga narrowed threshold range (the maximum threshold range that can segment mandible without manual efforts) was developed in 3D reconstruction, and compared with the traditional method. We used dilation operations to make up the information loss of image borders, by which we obtained an approxinate segment result. A precise segment resultwas eventually arrived with the help of logical operations and region growing. We compared mean time consumptions of the two methods, as well as their 3D reconstruction results using Geomagic Studio 11. 0. RESULTS: The new method generated a success rate of 91. 67% (11/12), with a mean time consumption of (319. 7±125. 3) s. The traditional method took much longer time [(1,261. 3±427. 3) s, P<0. 05] than the new method. Compared with the reconstruction results of traditional method, the new method had an outward deviation of (0. 066±0. 011) mm and an inward deviation of (0. 070±0. 008) mm. Such deviations were less than the minimum distance that a naked eye can discern. The lower limit of the widest threshold range which mandible could be isolated was (507. 72± 100. 31) HU, while the upper limit was (1,133. 33±47. 57) HU. CONCLUSION: The new method we proposed can improve the efficiency of threshold segmentation of mandible.

Primary hepatic neuroendocrine tumor with multiple liver metastases: A case report with review of the literature.

We herein present a case involving a 41-year-old woman in whom ultrasound examination revealed multiple liver hemangiomas more than 3 years ago. Follow-up ultrasound examination revealed that the masses had significantly increased; the largest was located in the right lobe (about 8.2 cm × 7.4 cm × 6.0 cm). Abdominal multidetector computed tomography revealed multiple well-circumscribed, heterogeneous, hypodense masses (largest, 6.4 cm × 6.3 cm × 5.0 cm) with significant contrast enhancement during the arterial and portal phases and with contrast wash-out and peripheral enhancement during the delayed phases. Magnetic resonance images demonstrated multiple well-circumscribed, heterogeneous, hypointense hepatic masses with significant contrast enhancement (largest, 6.4 cm × 6.5 cm × 5.1 cm); multiple enlarged porta lymph nodes; and multiple slightly enlarged retroperitoneal lymph nodes. Histological and immunohistochemical examination of the right mass biopsy specimen suggested a malignant neoplasm that had originated from a neuroendocrine cell type (grade 2 well-differentiated neuroendocrine carcinoma). After performing a systemic examination to exclude metastasis from an extrahepatic primary site, we considered that the masses had arisen from a primary hepatic neuroendocrine tumor with multiple liver metastases. The patient underwent transcatheter arterial chemoembolization using a combination of oxaliplatin (150 mg) mixed with one bottle of gelatin sponge particles (560-710 µm) and lipiodol (6 mL). Primary neuroendocrine tumors of the liver are extremely rare. This case is interesting because of the rarity of this neoplasm and previous misdiagnosis as multiple liver hemangiomas. Previously reported cases in the literature are also reviewed.

Role of EZH2 protein expression in gastric carcinogenesis among Asians: a meta-analysis.

The present meta-analysis aggregated the results of relevant studies to identify the role of zeste homolog 2 (EZH2) expression in gastric carcinogenesis among Asians. Related articles were found by searching the following electronic databases without language restrictions: PubMed, SpringerLink, Karger Medical and Scientific Publishers, Chinese Biomedical Database (CBM), Chinese National Knowledge Infrastructure (CNKI), and Google Scholar. Meta-analysis was performed using STATA statistical software. Crude odds ratios (ORs) or hazard ratios (HRs) with their corresponding 95 % confidence interval (95 % CI) were calculated. Ten relevant studies, which enrolled a total of 872 gastric cancer patients, were selected for statistical analysis. The most important findings of our meta-analysis was that cancer tissues exhibited higher expression levels of EZH2 protein than normal, adjacent and benign tissues (cancer tissues vs normal tissues: OR = 32.15, 95 % CI 22.58 ~ 45.79, P < 0.001; cancer tissues vs adjacent tissues: OR = 16.10, 95 % CI 11.35 ~ 22.84, P < 0.001; cancer tissues vs benign tissues: OR = 2.66, 95 % CI 1.89 ~ 3.75, P < 0.001; respectively). Furthermore, we observed positive correlations between EZH2 expression and the TNM stage (OR = 2.86, 95 % CI 1.72 ~ 4.75, P < 0.001) as well as lymph node metastasis (OR = 3.02, 95 % CI 2.01 ~ 4.53, P < 0.001) of patients with gastric carcinoma. The correlation between EZH2 expression and gastric cancer prognosis was also evaluated in the meta-analysis. Statistical analysis demonstrated that the overall survival (OS) of EZH2-negative patients was shorter than that of patients with positive expressions of EZH2 (HR = 0.54, 95 % CI = 0.05 ~ 1.03, P = 0.032). Our meta-analysis confirmed the view that EZH2 expression might participate in the development of gastric carcinogenesis. Thus, EZH2 protein may be a valuable biomarker for the diagnosis and prognosis of gastric cancer.

[Effects of Jinlong Capsule on expressions of interleukin-2 and soluble interleukin-2 receptor in patients with primary liver cancer after transarterial chemoembolization therapy].

OBJECTIVE: To observe and discuss the dynamic changes of interleukin-2 (IL-2) and soluble interleukin-2 receptor (sIL-2R) and their significance in the patients with primary liver cancer after transarterial chemoembolization (TACE) therapy combined with Jinglong Capsule. METHODS: A total of 48 patients with primary liver cancer, who failed to be treated by major surgery, were randomly divided into two groups: Jinlong Capsule group (TACE therapy plus Jinlong Capsule) and control group (TACE therapy alone). There were 24 cases in each group. The levels of peripheral blood IL-2 and slL-2R were measured before the first TACE and 1, 7 and 15 days after the second TACE respectively by using double-antibody sandwich enzyme-linked immunosorbent assay. The data from Jinlong Capsule group were compared with those from the control group. RESULTS: The level of sIL-2R in Jinlong Capsule group was significantly lower than that in the control group (P<0.05), while the level of IL-2 was significantly higher than that in the control group (P<0.05). CONCLUSION: Jinlong Capsule can significantly improve the lymphocyte function of the patients with primary liver cancer after TACE. The levels of IL-2 and sIL-2R can be considered as the valuable parameters for evaluating the effects on primary liver cancer, and Jinlong Capsule is helpful for the patients with primary liver cancer.